From 6d24c40b6e79176b05ec735adcecfd346b03f059 Mon Sep 17 00:00:00 2001
From: Veikka Tuominen <git@vexu.eu>
Date: Thu, 30 Jun 2022 16:10:15 +0300
Subject: [PATCH 1/7] Sema: improve bitcast to enum error

---
 src/Sema.zig                                  | 20 +++++++++++++++----
 .../compile_errors/bitCast_to_enum_type.zig   | 12 +++++++++++
 .../stage1/obj/bitCast_to_enum_type.zig       | 10 ----------
 3 files changed, 28 insertions(+), 14 deletions(-)
 create mode 100644 test/cases/compile_errors/bitCast_to_enum_type.zig
 delete mode 100644 test/cases/compile_errors/stage1/obj/bitCast_to_enum_type.zig

diff --git a/src/Sema.zig b/src/Sema.zig
index 862d5cbf48..08372bf7b3 100644
--- a/src/Sema.zig
+++ b/src/Sema.zig
@@ -7617,11 +7617,11 @@ fn zirBitcast(sema: *Sema, block: *Block, inst: Zir.Inst.Index) CompileError!Air
     const extra = sema.code.extraData(Zir.Inst.Bin, inst_data.payload_index).data;
 
     const dest_ty = try sema.resolveType(block, dest_ty_src, extra.lhs);
+    const operand = try sema.resolveInst(extra.rhs);
     switch (dest_ty.zigTypeTag()) {
         .AnyFrame,
         .ComptimeFloat,
         .ComptimeInt,
-        .Enum,
         .EnumLiteral,
         .ErrorSet,
         .ErrorUnion,
@@ -7634,7 +7634,21 @@ fn zirBitcast(sema: *Sema, block: *Block, inst: Zir.Inst.Index) CompileError!Air
         .Type,
         .Undefined,
         .Void,
-        => return sema.fail(block, dest_ty_src, "invalid type '{}' for @bitCast", .{dest_ty.fmt(sema.mod)}),
+        => return sema.fail(block, dest_ty_src, "cannot @bitCast to '{}'", .{dest_ty.fmt(sema.mod)}),
+
+        .Enum => {
+            const msg = msg: {
+                const msg = try sema.errMsg(block, dest_ty_src, "cannot @bitCast to '{}'", .{dest_ty.fmt(sema.mod)});
+                errdefer msg.destroy(sema.gpa);
+                switch (sema.typeOf(operand).zigTypeTag()) {
+                    .Int, .ComptimeInt => try sema.errNote(block, dest_ty_src, msg, "use @intToEnum for type coercion", .{}),
+                    else => {},
+                }
+
+                break :msg msg;
+            };
+            return sema.failWithOwnedErrorMsg(block, msg);
+        },
 
         .Pointer => return sema.fail(block, dest_ty_src, "cannot @bitCast to '{}', use @ptrCast to cast to a pointer", .{
             dest_ty.fmt(sema.mod),
@@ -7658,8 +7672,6 @@ fn zirBitcast(sema: *Sema, block: *Block, inst: Zir.Inst.Index) CompileError!Air
         .Vector,
         => {},
     }
-
-    const operand = try sema.resolveInst(extra.rhs);
     return sema.bitCast(block, dest_ty, operand, operand_src);
 }
 
diff --git a/test/cases/compile_errors/bitCast_to_enum_type.zig b/test/cases/compile_errors/bitCast_to_enum_type.zig
new file mode 100644
index 0000000000..add531627f
--- /dev/null
+++ b/test/cases/compile_errors/bitCast_to_enum_type.zig
@@ -0,0 +1,12 @@
+export fn entry() void {
+    const E = enum(u32) { a, b };
+    const y = @bitCast(E, @as(u32, 3));
+    _ = y;
+}
+
+// error
+// backend=stage2
+// target=native
+//
+// :3:24: error: cannot @bitCast to 'tmp.entry.E'
+// :3:24: note: use @intToEnum for type coercion
diff --git a/test/cases/compile_errors/stage1/obj/bitCast_to_enum_type.zig b/test/cases/compile_errors/stage1/obj/bitCast_to_enum_type.zig
deleted file mode 100644
index 4d63ab9e01..0000000000
--- a/test/cases/compile_errors/stage1/obj/bitCast_to_enum_type.zig
+++ /dev/null
@@ -1,10 +0,0 @@
-export fn entry() void {
-    const y = @bitCast(enum(u32) { a, b }, @as(u32, 3));
-    _ = y;
-}
-
-// error
-// backend=stage1
-// target=native
-//
-// tmp.zig:2:24: error: cannot cast a value of type 'y'

From 3014a0d5f1dcbcfdcec3852ffd54f3c589fe3e83 Mon Sep 17 00:00:00 2001
From: Veikka Tuominen <git@vexu.eu>
Date: Thu, 30 Jun 2022 16:39:54 +0300
Subject: [PATCH 2/7] Sema: validate callconv

---
 src/Sema.zig                                  | 40 +++++++++++++++++++
 .../{stage1/obj => }/bogus_compile_var.zig    |  4 +-
 ...aapcs_aapcsvfp_on_unsupported_platform.zig | 11 +++++
 ...conv_interrupt_on_unsupported_platform.zig |  7 ++++
 ...allconv_signal_on_unsupported_platform.zig |  7 ++++
 ...call_thiscall_on_unsupported_platform.zig} |  8 ++--
 ...onv_vectorcall_on_unsupported_platform.zig |  7 ++++
 ...aapcs_aapcsvfp_on_unsupported_platform.zig | 11 -----
 ...conv_interrupt_on_unsupported_platform.zig |  7 ----
 ...allconv_signal_on_unsupported_platform.zig |  7 ----
 ...all_thiscall_on_unsupported_platform-1.zig | 11 -----
 ...onv_vectorcall_on_unsupported_platform.zig |  7 ----
 12 files changed, 78 insertions(+), 49 deletions(-)
 rename test/cases/compile_errors/{stage1/obj => }/bogus_compile_var.zig (57%)
 create mode 100644 test/cases/compile_errors/callconv_apcs_aapcs_aapcsvfp_on_unsupported_platform.zig
 create mode 100644 test/cases/compile_errors/callconv_interrupt_on_unsupported_platform.zig
 create mode 100644 test/cases/compile_errors/callconv_signal_on_unsupported_platform.zig
 rename test/cases/compile_errors/{stage1/obj/callconv_stdcall_fastcall_thiscall_on_unsupported_platform-0.zig => callconv_stdcall_fastcall_thiscall_on_unsupported_platform.zig} (58%)
 create mode 100644 test/cases/compile_errors/callconv_vectorcall_on_unsupported_platform.zig
 delete mode 100644 test/cases/compile_errors/stage1/obj/callconv_apcs_aapcs_aapcsvfp_on_unsupported_platform.zig
 delete mode 100644 test/cases/compile_errors/stage1/obj/callconv_interrupt_on_unsupported_platform.zig
 delete mode 100644 test/cases/compile_errors/stage1/obj/callconv_signal_on_unsupported_platform.zig
 delete mode 100644 test/cases/compile_errors/stage1/obj/callconv_stdcall_fastcall_thiscall_on_unsupported_platform-1.zig
 delete mode 100644 test/cases/compile_errors/stage1/obj/callconv_vectorcall_on_unsupported_platform.zig

diff --git a/src/Sema.zig b/src/Sema.zig
index 08372bf7b3..0d568f8b38 100644
--- a/src/Sema.zig
+++ b/src/Sema.zig
@@ -7007,6 +7007,7 @@ fn funcCommon(
     noalias_bits: u32,
 ) CompileError!Air.Inst.Ref {
     const ret_ty_src: LazySrcLoc = .{ .node_offset_fn_type_ret_ty = src_node_offset };
+    const cc_src: LazySrcLoc = .{ .node_offset_fn_type_cc = src_node_offset };
 
     var is_generic = bare_return_type.tag() == .generic_poison or
         alignment == null or
@@ -7109,6 +7110,45 @@ fn funcCommon(
         const cc_workaround = cc orelse .Unspecified;
         const align_workaround = alignment orelse 0;
 
+        const arch = sema.mod.getTarget().cpu.arch;
+        if (switch (cc_workaround) {
+            .Unspecified, .C, .Naked, .Async, .Inline => null,
+            .Interrupt => switch (arch) {
+                .i386, .x86_64, .avr, .msp430 => null,
+                else => @as([]const u8, "i386, x86_64, AVR, and MSP430"),
+            },
+            .Signal => switch (arch) {
+                .avr => null,
+                else => @as([]const u8, "AVR"),
+            },
+            .Stdcall, .Fastcall, .Thiscall => switch (arch) {
+                .i386 => null,
+                else => @as([]const u8, "i386"),
+            },
+            .Vectorcall => switch (arch) {
+                .i386, .aarch64, .aarch64_be, .aarch64_32 => null,
+                else => @as([]const u8, "i386 and AArch64"),
+            },
+            .APCS, .AAPCS, .AAPCSVFP => switch (arch) {
+                .arm, .armeb, .aarch64, .aarch64_be, .aarch64_32 => null,
+                else => @as([]const u8, "ARM"),
+            },
+            .SysV, .Win64 => switch (arch) {
+                .x86_64 => null,
+                else => @as([]const u8, "x86_64"),
+            },
+            .PtxKernel => switch (arch) {
+                .nvptx, .nvptx64 => null,
+                else => @as([]const u8, "nvptx and nvptx64"),
+            },
+        }) |allowed_platform| {
+            return sema.fail(block, cc_src, "callconv '{s}' is only available on {s}, not {s}", .{
+                @tagName(cc_workaround),
+                allowed_platform,
+                @tagName(arch),
+            });
+        }
+
         break :fn_ty try Type.Tag.function.create(sema.arena, .{
             .param_types = param_types,
             .comptime_params = comptime_params.ptr,
diff --git a/test/cases/compile_errors/stage1/obj/bogus_compile_var.zig b/test/cases/compile_errors/bogus_compile_var.zig
similarity index 57%
rename from test/cases/compile_errors/stage1/obj/bogus_compile_var.zig
rename to test/cases/compile_errors/bogus_compile_var.zig
index 845d943c7d..28d8b1dba5 100644
--- a/test/cases/compile_errors/stage1/obj/bogus_compile_var.zig
+++ b/test/cases/compile_errors/bogus_compile_var.zig
@@ -2,7 +2,7 @@ const x = @import("builtin").bogus;
 export fn entry() usize { return @sizeOf(@TypeOf(x)); }
 
 // error
-// backend=stage1
+// backend=stage2
 // target=native
 //
-// tmp.zig:1:29: error: container 'builtin' has no member called 'bogus'
+// :1:29: error: struct 'builtin.builtin' has no member named 'bogus'
diff --git a/test/cases/compile_errors/callconv_apcs_aapcs_aapcsvfp_on_unsupported_platform.zig b/test/cases/compile_errors/callconv_apcs_aapcs_aapcsvfp_on_unsupported_platform.zig
new file mode 100644
index 0000000000..cc6fc59a1a
--- /dev/null
+++ b/test/cases/compile_errors/callconv_apcs_aapcs_aapcsvfp_on_unsupported_platform.zig
@@ -0,0 +1,11 @@
+export fn entry1() callconv(.APCS) void {}
+export fn entry2() callconv(.AAPCS) void {}
+export fn entry3() callconv(.AAPCSVFP) void {}
+
+// error
+// backend=stage2
+// target=x86_64-linux-none
+//
+// :1:30: error: callconv 'APCS' is only available on ARM, not x86_64
+// :2:30: error: callconv 'AAPCS' is only available on ARM, not x86_64
+// :3:30: error: callconv 'AAPCSVFP' is only available on ARM, not x86_64
diff --git a/test/cases/compile_errors/callconv_interrupt_on_unsupported_platform.zig b/test/cases/compile_errors/callconv_interrupt_on_unsupported_platform.zig
new file mode 100644
index 0000000000..5f11fdcfa8
--- /dev/null
+++ b/test/cases/compile_errors/callconv_interrupt_on_unsupported_platform.zig
@@ -0,0 +1,7 @@
+export fn entry() callconv(.Interrupt) void {}
+
+// error
+// backend=stage2
+// target=aarch64-linux-none
+//
+// :1:29: error: callconv 'Interrupt' is only available on i386, x86_64, AVR, and MSP430, not aarch64
diff --git a/test/cases/compile_errors/callconv_signal_on_unsupported_platform.zig b/test/cases/compile_errors/callconv_signal_on_unsupported_platform.zig
new file mode 100644
index 0000000000..9233655e35
--- /dev/null
+++ b/test/cases/compile_errors/callconv_signal_on_unsupported_platform.zig
@@ -0,0 +1,7 @@
+export fn entry() callconv(.Signal) void {}
+
+// error
+// backend=stage2
+// target=x86_64-linux-none
+//
+// :1:29: error: callconv 'Signal' is only available on AVR, not x86_64
diff --git a/test/cases/compile_errors/stage1/obj/callconv_stdcall_fastcall_thiscall_on_unsupported_platform-0.zig b/test/cases/compile_errors/callconv_stdcall_fastcall_thiscall_on_unsupported_platform.zig
similarity index 58%
rename from test/cases/compile_errors/stage1/obj/callconv_stdcall_fastcall_thiscall_on_unsupported_platform-0.zig
rename to test/cases/compile_errors/callconv_stdcall_fastcall_thiscall_on_unsupported_platform.zig
index f4994107cd..d22fd13e8a 100644
--- a/test/cases/compile_errors/stage1/obj/callconv_stdcall_fastcall_thiscall_on_unsupported_platform-0.zig
+++ b/test/cases/compile_errors/callconv_stdcall_fastcall_thiscall_on_unsupported_platform.zig
@@ -15,9 +15,9 @@ export fn entry3() void {
 }
 
 // error
-// backend=stage1
+// backend=stage2
 // target=x86_64-linux-none
 //
-// tmp.zig:1:27: error: callconv 'Stdcall' is only available on x86, not x86_64
-// tmp.zig:2:27: error: callconv 'Fastcall' is only available on x86, not x86_64
-// tmp.zig:3:27: error: callconv 'Thiscall' is only available on x86, not x86_64
+// :1:28: error: callconv 'Stdcall' is only available on i386, not x86_64
+// :2:28: error: callconv 'Fastcall' is only available on i386, not x86_64
+// :3:28: error: callconv 'Thiscall' is only available on i386, not x86_64
diff --git a/test/cases/compile_errors/callconv_vectorcall_on_unsupported_platform.zig b/test/cases/compile_errors/callconv_vectorcall_on_unsupported_platform.zig
new file mode 100644
index 0000000000..9c231a6ea8
--- /dev/null
+++ b/test/cases/compile_errors/callconv_vectorcall_on_unsupported_platform.zig
@@ -0,0 +1,7 @@
+export fn entry() callconv(.Vectorcall) void {}
+
+// error
+// backend=stage2
+// target=x86_64-linux-none
+//
+// :1:29: error: callconv 'Vectorcall' is only available on i386 and AArch64, not x86_64
diff --git a/test/cases/compile_errors/stage1/obj/callconv_apcs_aapcs_aapcsvfp_on_unsupported_platform.zig b/test/cases/compile_errors/stage1/obj/callconv_apcs_aapcs_aapcsvfp_on_unsupported_platform.zig
deleted file mode 100644
index fa06287803..0000000000
--- a/test/cases/compile_errors/stage1/obj/callconv_apcs_aapcs_aapcsvfp_on_unsupported_platform.zig
+++ /dev/null
@@ -1,11 +0,0 @@
-export fn entry1() callconv(.APCS) void {}
-export fn entry2() callconv(.AAPCS) void {}
-export fn entry3() callconv(.AAPCSVFP) void {}
-
-// error
-// backend=stage1
-// target=x86_64-linux-none
-//
-// tmp.zig:1:29: error: callconv 'APCS' is only available on ARM, not x86_64
-// tmp.zig:2:29: error: callconv 'AAPCS' is only available on ARM, not x86_64
-// tmp.zig:3:29: error: callconv 'AAPCSVFP' is only available on ARM, not x86_64
diff --git a/test/cases/compile_errors/stage1/obj/callconv_interrupt_on_unsupported_platform.zig b/test/cases/compile_errors/stage1/obj/callconv_interrupt_on_unsupported_platform.zig
deleted file mode 100644
index 8304fb90c1..0000000000
--- a/test/cases/compile_errors/stage1/obj/callconv_interrupt_on_unsupported_platform.zig
+++ /dev/null
@@ -1,7 +0,0 @@
-export fn entry() callconv(.Interrupt) void {}
-
-// error
-// backend=stage1
-// target=aarch64-linux-none
-//
-// tmp.zig:1:28: error: callconv 'Interrupt' is only available on x86, x86_64, AVR, and MSP430, not aarch64
diff --git a/test/cases/compile_errors/stage1/obj/callconv_signal_on_unsupported_platform.zig b/test/cases/compile_errors/stage1/obj/callconv_signal_on_unsupported_platform.zig
deleted file mode 100644
index 4b19b188fd..0000000000
--- a/test/cases/compile_errors/stage1/obj/callconv_signal_on_unsupported_platform.zig
+++ /dev/null
@@ -1,7 +0,0 @@
-export fn entry() callconv(.Signal) void {}
-
-// error
-// backend=stage1
-// target=x86_64-linux-none
-//
-// tmp.zig:1:28: error: callconv 'Signal' is only available on AVR, not x86_64
diff --git a/test/cases/compile_errors/stage1/obj/callconv_stdcall_fastcall_thiscall_on_unsupported_platform-1.zig b/test/cases/compile_errors/stage1/obj/callconv_stdcall_fastcall_thiscall_on_unsupported_platform-1.zig
deleted file mode 100644
index aa23f9ae51..0000000000
--- a/test/cases/compile_errors/stage1/obj/callconv_stdcall_fastcall_thiscall_on_unsupported_platform-1.zig
+++ /dev/null
@@ -1,11 +0,0 @@
-export fn entry1() callconv(.Stdcall) void {}
-export fn entry2() callconv(.Fastcall) void {}
-export fn entry3() callconv(.Thiscall) void {}
-
-// error
-// backend=stage1
-// target=x86_64-linux-none
-//
-// tmp.zig:1:29: error: callconv 'Stdcall' is only available on x86, not x86_64
-// tmp.zig:2:29: error: callconv 'Fastcall' is only available on x86, not x86_64
-// tmp.zig:3:29: error: callconv 'Thiscall' is only available on x86, not x86_64
diff --git a/test/cases/compile_errors/stage1/obj/callconv_vectorcall_on_unsupported_platform.zig b/test/cases/compile_errors/stage1/obj/callconv_vectorcall_on_unsupported_platform.zig
deleted file mode 100644
index e60e6ab42c..0000000000
--- a/test/cases/compile_errors/stage1/obj/callconv_vectorcall_on_unsupported_platform.zig
+++ /dev/null
@@ -1,7 +0,0 @@
-export fn entry() callconv(.Vectorcall) void {}
-
-// error
-// backend=stage1
-// target=x86_64-linux-none
-//
-// tmp.zig:1:28: error: callconv 'Vectorcall' is only available on x86 and AArch64, not x86_64

From 3c73f711771e41e9176e973c64484f0ce5e0eeed Mon Sep 17 00:00:00 2001
From: Veikka Tuominen <git@vexu.eu>
Date: Thu, 30 Jun 2022 16:58:46 +0300
Subject: [PATCH 3/7] Sema: prefer func.onwer_decl for compilelog src

---
 src/Sema.zig                                                | 3 ++-
 .../{stage1/obj => }/compile-time_division_by_zero.zig      | 4 ++--
 .../obj => }/compile-time_remainder_division_by_zero.zig    | 4 ++--
 .../compileLog_of_tagged_enum_doesnt_crash_the_compiler.zig | 6 +++---
 test/cases/compile_errors/{stage1/obj => }/compile_log.zig  | 6 ++----
 ...ent_inside_function_which_must_be_comptime_evaluated.zig | 4 ++--
 .../{stage1/obj => }/compile_time_division_by_zero.zig      | 5 +++--
 7 files changed, 16 insertions(+), 16 deletions(-)
 rename test/cases/compile_errors/{stage1/obj => }/compile-time_division_by_zero.zig (58%)
 rename test/cases/compile_errors/{stage1/obj => }/compile-time_remainder_division_by_zero.zig (58%)
 rename test/cases/compile_errors/{stage1/obj => }/compileLog_of_tagged_enum_doesnt_crash_the_compiler.zig (66%)
 rename test/cases/compile_errors/{stage1/obj => }/compile_log.zig (54%)
 rename test/cases/compile_errors/{stage1/obj => }/compile_log_statement_inside_function_which_must_be_comptime_evaluated.zig (72%)
 rename test/cases/compile_errors/{stage1/obj => }/compile_time_division_by_zero.zig (56%)

diff --git a/src/Sema.zig b/src/Sema.zig
index 0d568f8b38..30cebe18b3 100644
--- a/src/Sema.zig
+++ b/src/Sema.zig
@@ -4272,7 +4272,8 @@ fn zirCompileLog(
     }
     try writer.print("\n", .{});
 
-    const gop = try sema.mod.compile_log_decls.getOrPut(sema.gpa, sema.owner_decl_index);
+    const decl_index = if (sema.func) |some| some.owner_decl else sema.owner_decl_index;
+    const gop = try sema.mod.compile_log_decls.getOrPut(sema.gpa, decl_index);
     if (!gop.found_existing) {
         gop.value_ptr.* = src_node;
     }
diff --git a/test/cases/compile_errors/stage1/obj/compile-time_division_by_zero.zig b/test/cases/compile_errors/compile-time_division_by_zero.zig
similarity index 58%
rename from test/cases/compile_errors/stage1/obj/compile-time_division_by_zero.zig
rename to test/cases/compile_errors/compile-time_division_by_zero.zig
index e16f5f8cf4..969598e500 100644
--- a/test/cases/compile_errors/stage1/obj/compile-time_division_by_zero.zig
+++ b/test/cases/compile_errors/compile-time_division_by_zero.zig
@@ -6,7 +6,7 @@ comptime {
 }
 
 // error
-// backend=stage1
+// backend=stage2
 // target=native
 //
-// tmp.zig:4:17: error: division by zero
+// :4:19: error: division by zero here causes undefined behavior
diff --git a/test/cases/compile_errors/stage1/obj/compile-time_remainder_division_by_zero.zig b/test/cases/compile_errors/compile-time_remainder_division_by_zero.zig
similarity index 58%
rename from test/cases/compile_errors/stage1/obj/compile-time_remainder_division_by_zero.zig
rename to test/cases/compile_errors/compile-time_remainder_division_by_zero.zig
index 63f0def52c..301fad6a68 100644
--- a/test/cases/compile_errors/stage1/obj/compile-time_remainder_division_by_zero.zig
+++ b/test/cases/compile_errors/compile-time_remainder_division_by_zero.zig
@@ -6,7 +6,7 @@ comptime {
 }
 
 // error
-// backend=stage1
+// backend=stage2
 // target=native
 //
-// tmp.zig:4:17: error: division by zero
+// :4:19: error: division by zero here causes undefined behavior
diff --git a/test/cases/compile_errors/stage1/obj/compileLog_of_tagged_enum_doesnt_crash_the_compiler.zig b/test/cases/compile_errors/compileLog_of_tagged_enum_doesnt_crash_the_compiler.zig
similarity index 66%
rename from test/cases/compile_errors/stage1/obj/compileLog_of_tagged_enum_doesnt_crash_the_compiler.zig
rename to test/cases/compile_errors/compileLog_of_tagged_enum_doesnt_crash_the_compiler.zig
index 36e1ee1118..9189eeb48d 100644
--- a/test/cases/compile_errors/stage1/obj/compileLog_of_tagged_enum_doesnt_crash_the_compiler.zig
+++ b/test/cases/compile_errors/compileLog_of_tagged_enum_doesnt_crash_the_compiler.zig
@@ -6,12 +6,12 @@ fn testCompileLog(x: Bar) void {
     @compileLog(x);
 }
 
-pub fn main () void {
+pub export fn entry() void {
     comptime testCompileLog(Bar{.X = 123});
 }
 
 // error
-// backend=stage1
+// backend=stage2
 // target=native
 //
-// tmp.zig:6:5: error: found compile log statement
+// :6:5: error: found compile log statement
diff --git a/test/cases/compile_errors/stage1/obj/compile_log.zig b/test/cases/compile_errors/compile_log.zig
similarity index 54%
rename from test/cases/compile_errors/stage1/obj/compile_log.zig
rename to test/cases/compile_errors/compile_log.zig
index 7f5d522407..281f8747d2 100644
--- a/test/cases/compile_errors/stage1/obj/compile_log.zig
+++ b/test/cases/compile_errors/compile_log.zig
@@ -8,9 +8,7 @@ fn bar(a: i32, b: []const u8) void {
 }
 
 // error
-// backend=stage1
+// backend=llvm
 // target=native
 //
-// tmp.zig:5:5: error: found compile log statement
-// tmp.zig:6:5: error: found compile log statement
-// tmp.zig:7:5: error: found compile log statement
+// :5:5: error: found compile log statement
diff --git a/test/cases/compile_errors/stage1/obj/compile_log_statement_inside_function_which_must_be_comptime_evaluated.zig b/test/cases/compile_errors/compile_log_statement_inside_function_which_must_be_comptime_evaluated.zig
similarity index 72%
rename from test/cases/compile_errors/stage1/obj/compile_log_statement_inside_function_which_must_be_comptime_evaluated.zig
rename to test/cases/compile_errors/compile_log_statement_inside_function_which_must_be_comptime_evaluated.zig
index 19b96048cb..0bc45eae0a 100644
--- a/test/cases/compile_errors/stage1/obj/compile_log_statement_inside_function_which_must_be_comptime_evaluated.zig
+++ b/test/cases/compile_errors/compile_log_statement_inside_function_which_must_be_comptime_evaluated.zig
@@ -8,7 +8,7 @@ export fn entry() void {
 }
 
 // error
-// backend=stage1
+// backend=stage2
 // target=native
 //
-// tmp.zig:2:5: error: found compile log statement
+// :2:5: error: found compile log statement
diff --git a/test/cases/compile_errors/stage1/obj/compile_time_division_by_zero.zig b/test/cases/compile_errors/compile_time_division_by_zero.zig
similarity index 56%
rename from test/cases/compile_errors/stage1/obj/compile_time_division_by_zero.zig
rename to test/cases/compile_errors/compile_time_division_by_zero.zig
index 7f7e168f02..281ccf28a1 100644
--- a/test/cases/compile_errors/stage1/obj/compile_time_division_by_zero.zig
+++ b/test/cases/compile_errors/compile_time_division_by_zero.zig
@@ -6,7 +6,8 @@ fn foo(x: u32) u32 {
 export fn entry() usize { return @sizeOf(@TypeOf(y)); }
 
 // error
-// backend=stage1
+// backend=llvm
 // target=native
 //
-// tmp.zig:3:14: error: division by zero
+// :3:16: error: division by zero here causes undefined behavior
+// :1:14: note: called from here

From ae7b32eb62cb00a09fe2e0e30b307eb83e9f0a86 Mon Sep 17 00:00:00 2001
From: Veikka Tuominen <git@vexu.eu>
Date: Thu, 30 Jun 2022 17:22:16 +0300
Subject: [PATCH 4/7] Sema: validate deref operator type and value

---
 lib/c.zig                                     |  2 +-
 lib/std/os.zig                                |  2 +-
 lib/std/process.zig                           |  2 +-
 src/AstGen.zig                                |  2 ++
 src/Sema.zig                                  | 27 +++++++++++++++++++
 src/Zir.zig                                   |  6 +++++
 src/print_zir.zig                             |  1 +
 .../assign_to_invalid_dereference.zig         |  9 +++++++
 .../{stage1 => }/deref_on_undefined_value.zig |  4 +--
 .../deref_slice_and_get_len_field.zig         |  4 +--
 .../{stage1/obj => }/dereference_an_array.zig |  6 ++---
 .../compile_errors/dereference_slice.zig      | 12 +++++++++
 .../dereference_unknown_length_pointer.zig    |  9 +++++++
 .../invalid_deref_on_switch_target.zig        |  4 +--
 .../invalid_multiple_dereferences.zig         |  6 ++---
 .../comptime_ptrcast_of_zero-sized_type.zig   |  0
 .../obj/assign_to_invalid_dereference.zig     |  9 -------
 .../dereference_unknown_length_pointer.zig    |  9 -------
 .../obj/take_slice_of_invalid_dereference.zig | 10 -------
 .../take_slice_of_invalid_dereference.zig     | 10 +++++++
 20 files changed, 91 insertions(+), 43 deletions(-)
 create mode 100644 test/cases/compile_errors/assign_to_invalid_dereference.zig
 rename test/cases/compile_errors/{stage1 => }/deref_on_undefined_value.zig (51%)
 rename test/cases/compile_errors/{stage1/obj => }/deref_slice_and_get_len_field.zig (53%)
 rename test/cases/compile_errors/{stage1/obj => }/dereference_an_array.zig (52%)
 create mode 100644 test/cases/compile_errors/dereference_slice.zig
 create mode 100644 test/cases/compile_errors/dereference_unknown_length_pointer.zig
 rename test/cases/compile_errors/{stage1/obj => }/invalid_deref_on_switch_target.zig (68%)
 rename test/cases/compile_errors/{stage1/obj => }/invalid_multiple_dereferences.zig (61%)
 rename test/cases/compile_errors/stage1/{obj => }/comptime_ptrcast_of_zero-sized_type.zig (100%)
 delete mode 100644 test/cases/compile_errors/stage1/obj/assign_to_invalid_dereference.zig
 delete mode 100644 test/cases/compile_errors/stage1/obj/dereference_unknown_length_pointer.zig
 delete mode 100644 test/cases/compile_errors/stage1/obj/take_slice_of_invalid_dereference.zig
 create mode 100644 test/cases/compile_errors/take_slice_of_invalid_dereference.zig

diff --git a/lib/c.zig b/lib/c.zig
index 30c6e0cd76..9df1b3fb01 100644
--- a/lib/c.zig
+++ b/lib/c.zig
@@ -82,7 +82,7 @@ fn memset(dest: ?[*]u8, c: u8, len: usize) callconv(.C) ?[*]u8 {
         var d = dest.?;
         var n = len;
         while (true) {
-            d.* = c;
+            d[0] = c;
             n -= 1;
             if (n == 0) break;
             d += 1;
diff --git a/lib/std/os.zig b/lib/std/os.zig
index 578a8ddcbc..02ed710dd3 100644
--- a/lib/std/os.zig
+++ b/lib/std/os.zig
@@ -1868,7 +1868,7 @@ pub fn getenv(key: []const u8) ?[]const u8 {
         }
         // Search the entire `environ` because we don't have a null terminated pointer.
         var ptr = std.c.environ;
-        while (ptr.*) |line| : (ptr += 1) {
+        while (ptr[0]) |line| : (ptr += 1) {
             var line_i: usize = 0;
             while (line[line_i] != 0 and line[line_i] != '=') : (line_i += 1) {}
             const this_key = line[0..line_i];
diff --git a/lib/std/process.zig b/lib/std/process.zig
index 0b64b5910d..dffd6b1701 100644
--- a/lib/std/process.zig
+++ b/lib/std/process.zig
@@ -313,7 +313,7 @@ pub fn getEnvMap(allocator: Allocator) !EnvMap {
         return result;
     } else if (builtin.link_libc) {
         var ptr = std.c.environ;
-        while (ptr.*) |line| : (ptr += 1) {
+        while (ptr[0]) |line| : (ptr += 1) {
             var line_i: usize = 0;
             while (line[line_i] != 0 and line[line_i] != '=') : (line_i += 1) {}
             const key = line[0..line_i];
diff --git a/src/AstGen.zig b/src/AstGen.zig
index c9abb1859b..8707728313 100644
--- a/src/AstGen.zig
+++ b/src/AstGen.zig
@@ -812,6 +812,7 @@ fn expr(gz: *GenZir, scope: *Scope, rl: ResultLoc, node: Ast.Node.Index) InnerEr
 
         .deref => {
             const lhs = try expr(gz, scope, .none, node_datas[node].lhs);
+            _ = try gz.addUnTok(.validate_deref, lhs, main_tokens[node]);
             switch (rl) {
                 .ref => return lhs,
                 else => {
@@ -2500,6 +2501,7 @@ fn unusedResultExpr(gz: *GenZir, scope: *Scope, statement: Ast.Node.Index) Inner
             .memset,
             .validate_array_init_ty,
             .validate_struct_init_ty,
+            .validate_deref,
             => break :b true,
         }
     } else switch (maybe_unused_result) {
diff --git a/src/Sema.zig b/src/Sema.zig
index 30cebe18b3..0e7188a6c9 100644
--- a/src/Sema.zig
+++ b/src/Sema.zig
@@ -1080,6 +1080,11 @@ fn analyzeBodyInner(
                 i += 1;
                 continue;
             },
+            .validate_deref => {
+                try sema.zirValidateDeref(block, inst);
+                i += 1;
+                continue;
+            },
             .@"export" => {
                 try sema.zirExport(block, inst);
                 i += 1;
@@ -3849,6 +3854,28 @@ fn zirValidateArrayInit(
     }
 }
 
+fn zirValidateDeref(sema: *Sema, block: *Block, inst: Zir.Inst.Index) CompileError!void {
+    const inst_data = sema.code.instructions.items(.data)[inst].un_tok;
+    const src = inst_data.src();
+    const operand_src: LazySrcLoc = .{ .token_offset = inst_data.src_tok + 1 };
+    const operand = try sema.resolveInst(inst_data.operand);
+    const operand_ty = sema.typeOf(operand);
+
+    if (operand_ty.zigTypeTag() != .Pointer) {
+        return sema.fail(block, src, "cannot dereference non-pointer type '{}'", .{operand_ty.fmt(sema.mod)});
+    } else switch (operand_ty.ptrSize()) {
+        .One, .C => {},
+        .Many => return sema.fail(block, src, "index syntax required for unknown-length pointer type '{}'", .{operand_ty.fmt(sema.mod)}),
+        .Slice => return sema.fail(block, src, "index syntax required for slice type '{}'", .{operand_ty.fmt(sema.mod)}),
+    }
+
+    if (try sema.resolveMaybeUndefVal(block, operand_src, operand)) |val| {
+        if (val.isUndef()) {
+            return sema.fail(block, src, "cannot dereference undefined value", .{});
+        }
+    }
+}
+
 fn failWithBadMemberAccess(
     sema: *Sema,
     block: *Block,
diff --git a/src/Zir.zig b/src/Zir.zig
index e6acfe8ed2..26bb09860d 100644
--- a/src/Zir.zig
+++ b/src/Zir.zig
@@ -729,6 +729,9 @@ pub const Inst = struct {
         /// Same as `validate_array_init` but additionally communicates that the
         /// resulting array initialization value is within a comptime scope.
         validate_array_init_comptime,
+        /// Check that operand type supports the dereference operand (.*).
+        /// Uses the `un_tok` field.
+        validate_deref,
         /// A struct literal with a specified type, with no fields.
         /// Uses the `un_node` field.
         struct_init_empty,
@@ -1156,6 +1159,7 @@ pub const Inst = struct {
                 .validate_struct_init_comptime,
                 .validate_array_init,
                 .validate_array_init_comptime,
+                .validate_deref,
                 .struct_init_empty,
                 .struct_init,
                 .struct_init_ref,
@@ -1309,6 +1313,7 @@ pub const Inst = struct {
                 .validate_struct_init_comptime,
                 .validate_array_init,
                 .validate_array_init_comptime,
+                .validate_deref,
                 .@"export",
                 .export_value,
                 .set_cold,
@@ -1709,6 +1714,7 @@ pub const Inst = struct {
                 .validate_struct_init_comptime = .pl_node,
                 .validate_array_init = .pl_node,
                 .validate_array_init_comptime = .pl_node,
+                .validate_deref = .un_tok,
                 .struct_init_empty = .un_node,
                 .field_type = .pl_node,
                 .field_type_ref = .pl_node,
diff --git a/src/print_zir.zig b/src/print_zir.zig
index 480a3e2a4f..fe8446b34a 100644
--- a/src/print_zir.zig
+++ b/src/print_zir.zig
@@ -242,6 +242,7 @@ const Writer = struct {
             .ret_tok,
             .ensure_err_payload_void,
             .closure_capture,
+            .validate_deref,
             => try self.writeUnTok(stream, inst),
 
             .bool_br_and,
diff --git a/test/cases/compile_errors/assign_to_invalid_dereference.zig b/test/cases/compile_errors/assign_to_invalid_dereference.zig
new file mode 100644
index 0000000000..cb35004034
--- /dev/null
+++ b/test/cases/compile_errors/assign_to_invalid_dereference.zig
@@ -0,0 +1,9 @@
+export fn entry() void {
+    'a'.* = 1;
+}
+
+// error
+// backend=stage2
+// target=native
+//
+// :2:8: error: cannot dereference non-pointer type 'comptime_int'
diff --git a/test/cases/compile_errors/stage1/deref_on_undefined_value.zig b/test/cases/compile_errors/deref_on_undefined_value.zig
similarity index 51%
rename from test/cases/compile_errors/stage1/deref_on_undefined_value.zig
rename to test/cases/compile_errors/deref_on_undefined_value.zig
index f64d567a26..fa12e2824c 100644
--- a/test/cases/compile_errors/stage1/deref_on_undefined_value.zig
+++ b/test/cases/compile_errors/deref_on_undefined_value.zig
@@ -4,7 +4,7 @@ comptime {
 }
 
 // error
-// backend=stage1
+// backend=stage2
 // target=native
 //
-// tmp.zig:3:9: error: attempt to dereference undefined value
+// :3:10: error: cannot dereference undefined value
diff --git a/test/cases/compile_errors/stage1/obj/deref_slice_and_get_len_field.zig b/test/cases/compile_errors/deref_slice_and_get_len_field.zig
similarity index 53%
rename from test/cases/compile_errors/stage1/obj/deref_slice_and_get_len_field.zig
rename to test/cases/compile_errors/deref_slice_and_get_len_field.zig
index 98097597cc..1ba03c6d50 100644
--- a/test/cases/compile_errors/stage1/obj/deref_slice_and_get_len_field.zig
+++ b/test/cases/compile_errors/deref_slice_and_get_len_field.zig
@@ -4,7 +4,7 @@ export fn entry() void {
 }
 
 // error
-// backend=stage1
+// backend=stage2
 // target=native
 //
-// tmp.zig:3:10: error: attempt to dereference non-pointer type '[]u8'
+// :3:10: error: index syntax required for slice type '[]u8'
diff --git a/test/cases/compile_errors/stage1/obj/dereference_an_array.zig b/test/cases/compile_errors/dereference_an_array.zig
similarity index 52%
rename from test/cases/compile_errors/stage1/obj/dereference_an_array.zig
rename to test/cases/compile_errors/dereference_an_array.zig
index 0dd91f70e5..f5aabf081c 100644
--- a/test/cases/compile_errors/stage1/obj/dereference_an_array.zig
+++ b/test/cases/compile_errors/dereference_an_array.zig
@@ -5,10 +5,10 @@ pub fn pass(in: []u8) []u8 {
     return out.*[0..1];
 }
 
-export fn entry() usize { return @sizeOf(@TypeOf(pass)); }
+export fn entry() usize { return @sizeOf(@TypeOf(&pass)); }
 
 // error
-// backend=stage1
+// backend=stage2
 // target=native
 //
-// tmp.zig:4:10: error: attempt to dereference non-pointer type '[10]u8'
+// :4:10: error: cannot dereference non-pointer type '[10]u8'
diff --git a/test/cases/compile_errors/dereference_slice.zig b/test/cases/compile_errors/dereference_slice.zig
new file mode 100644
index 0000000000..7dba3b55d8
--- /dev/null
+++ b/test/cases/compile_errors/dereference_slice.zig
@@ -0,0 +1,12 @@
+fn entry(x: []i32) i32 {
+    return x.*;
+}
+comptime {
+    _ = entry;
+}
+
+// error
+// backend=stage2
+// target=native
+//
+// :2:13: error: index syntax required for slice type '[]i32'
diff --git a/test/cases/compile_errors/dereference_unknown_length_pointer.zig b/test/cases/compile_errors/dereference_unknown_length_pointer.zig
new file mode 100644
index 0000000000..353f94b8d9
--- /dev/null
+++ b/test/cases/compile_errors/dereference_unknown_length_pointer.zig
@@ -0,0 +1,9 @@
+export fn entry(x: [*]i32) i32 {
+    return x.*;
+}
+
+// error
+// backend=stage2
+// target=native
+//
+// :2:13: error: index syntax required for unknown-length pointer type '[*]i32'
diff --git a/test/cases/compile_errors/stage1/obj/invalid_deref_on_switch_target.zig b/test/cases/compile_errors/invalid_deref_on_switch_target.zig
similarity index 68%
rename from test/cases/compile_errors/stage1/obj/invalid_deref_on_switch_target.zig
rename to test/cases/compile_errors/invalid_deref_on_switch_target.zig
index 966a881543..a880b16fca 100644
--- a/test/cases/compile_errors/stage1/obj/invalid_deref_on_switch_target.zig
+++ b/test/cases/compile_errors/invalid_deref_on_switch_target.zig
@@ -11,7 +11,7 @@ const Tile = enum {
 };
 
 // error
-// backend=stage1
+// backend=stage2
 // target=native
 //
-// tmp.zig:3:17: error: attempt to dereference non-pointer type 'Tile'
+// :3:17: error: cannot dereference non-pointer type 'tmp.Tile'
diff --git a/test/cases/compile_errors/stage1/obj/invalid_multiple_dereferences.zig b/test/cases/compile_errors/invalid_multiple_dereferences.zig
similarity index 61%
rename from test/cases/compile_errors/stage1/obj/invalid_multiple_dereferences.zig
rename to test/cases/compile_errors/invalid_multiple_dereferences.zig
index f8a0b8013f..3edebf7b1f 100644
--- a/test/cases/compile_errors/stage1/obj/invalid_multiple_dereferences.zig
+++ b/test/cases/compile_errors/invalid_multiple_dereferences.zig
@@ -12,8 +12,8 @@ pub const Box = struct {
 };
 
 // error
-// backend=stage1
+// backend=stage2
 // target=native
 //
-// tmp.zig:3:8: error: attempt to dereference non-pointer type 'Box'
-// tmp.zig:8:13: error: attempt to dereference non-pointer type 'Box'
+// :3:8: error: cannot dereference non-pointer type 'tmp.Box'
+// :8:13: error: cannot dereference non-pointer type 'tmp.Box'
diff --git a/test/cases/compile_errors/stage1/obj/comptime_ptrcast_of_zero-sized_type.zig b/test/cases/compile_errors/stage1/comptime_ptrcast_of_zero-sized_type.zig
similarity index 100%
rename from test/cases/compile_errors/stage1/obj/comptime_ptrcast_of_zero-sized_type.zig
rename to test/cases/compile_errors/stage1/comptime_ptrcast_of_zero-sized_type.zig
diff --git a/test/cases/compile_errors/stage1/obj/assign_to_invalid_dereference.zig b/test/cases/compile_errors/stage1/obj/assign_to_invalid_dereference.zig
deleted file mode 100644
index 7fef5db83c..0000000000
--- a/test/cases/compile_errors/stage1/obj/assign_to_invalid_dereference.zig
+++ /dev/null
@@ -1,9 +0,0 @@
-export fn entry() void {
-    'a'.* = 1;
-}
-
-// error
-// backend=stage1
-// target=native
-//
-// tmp.zig:2:8: error: attempt to dereference non-pointer type 'comptime_int'
diff --git a/test/cases/compile_errors/stage1/obj/dereference_unknown_length_pointer.zig b/test/cases/compile_errors/stage1/obj/dereference_unknown_length_pointer.zig
deleted file mode 100644
index c305e4bc98..0000000000
--- a/test/cases/compile_errors/stage1/obj/dereference_unknown_length_pointer.zig
+++ /dev/null
@@ -1,9 +0,0 @@
-export fn entry(x: [*]i32) i32 {
-    return x.*;
-}
-
-// error
-// backend=stage1
-// target=native
-//
-// tmp.zig:2:13: error: index syntax required for unknown-length pointer type '[*]i32'
diff --git a/test/cases/compile_errors/stage1/obj/take_slice_of_invalid_dereference.zig b/test/cases/compile_errors/stage1/obj/take_slice_of_invalid_dereference.zig
deleted file mode 100644
index c039be3737..0000000000
--- a/test/cases/compile_errors/stage1/obj/take_slice_of_invalid_dereference.zig
+++ /dev/null
@@ -1,10 +0,0 @@
-export fn entry() void {
-    const x = 'a'.*[0..];
-    _ = x;
-}
-
-// error
-// backend=stage1
-// target=native
-//
-// tmp.zig:2:18: error: attempt to dereference non-pointer type 'comptime_int'
diff --git a/test/cases/compile_errors/take_slice_of_invalid_dereference.zig b/test/cases/compile_errors/take_slice_of_invalid_dereference.zig
new file mode 100644
index 0000000000..35c1b2de0d
--- /dev/null
+++ b/test/cases/compile_errors/take_slice_of_invalid_dereference.zig
@@ -0,0 +1,10 @@
+export fn entry() void {
+    const x = 'a'.*[0..];
+    _ = x;
+}
+
+// error
+// backend=stage2
+// target=native
+//
+// :2:18: error: cannot dereference non-pointer type 'comptime_int'

From e6ebf56dd6cf2e2c23af952d2e9e327703c9cd02 Mon Sep 17 00:00:00 2001
From: Veikka Tuominen <git@vexu.eu>
Date: Thu, 30 Jun 2022 17:38:04 +0300
Subject: [PATCH 5/7] Sema: validate `@intToEnum` int operand type

---
 src/Sema.zig                                               | 7 ++++---
 .../{stage1/obj => }/discarding_error_value.zig            | 4 ++--
 .../{stage1/obj => }/duplicate_enum_field.zig              | 6 +++---
 .../{stage1/obj => }/duplicate_error_in_switch.zig         | 6 +++---
 .../obj => }/explicitly_casting_non_tag_type_to_enum.zig   | 4 ++--
 test/stage2/cbe.zig                                        | 4 ++--
 6 files changed, 16 insertions(+), 15 deletions(-)
 rename test/cases/compile_errors/{stage1/obj => }/discarding_error_value.zig (54%)
 rename test/cases/compile_errors/{stage1/obj => }/duplicate_enum_field.zig (56%)
 rename test/cases/compile_errors/{stage1/obj => }/duplicate_error_in_switch.zig (65%)
 rename test/cases/compile_errors/{stage1/obj => }/explicitly_casting_non_tag_type_to_enum.zig (71%)

diff --git a/src/Sema.zig b/src/Sema.zig
index 0e7188a6c9..64db6a9bed 100644
--- a/src/Sema.zig
+++ b/src/Sema.zig
@@ -2439,9 +2439,9 @@ fn zirEnumDecl(
             const field_src = enumFieldSrcLoc(sema.mod.declPtr(block.src_decl), tree.*, src.node_offset.x, field_i);
             const other_tag_src = enumFieldSrcLoc(sema.mod.declPtr(block.src_decl), tree.*, src.node_offset.x, gop.index);
             const msg = msg: {
-                const msg = try sema.errMsg(block, field_src, "duplicate enum tag", .{});
+                const msg = try sema.errMsg(block, field_src, "duplicate enum field '{s}'", .{field_name});
                 errdefer msg.destroy(gpa);
-                try sema.errNote(block, other_tag_src, msg, "other tag here", .{});
+                try sema.errNote(block, other_tag_src, msg, "other field here", .{});
                 break :msg msg;
             };
             return sema.failWithOwnedErrorMsg(block, msg);
@@ -2751,7 +2751,7 @@ fn zirEnsureResultNonError(sema: *Sema, block: *Block, inst: Zir.Inst.Index) Com
     const src = inst_data.src();
     const operand_ty = sema.typeOf(operand);
     switch (operand_ty.zigTypeTag()) {
-        .ErrorSet, .ErrorUnion => return sema.fail(block, src, "error is discarded", .{}),
+        .ErrorSet, .ErrorUnion => return sema.fail(block, src, "error is discardederror is discarded. consider using `try`, `catch`, or `if`", .{}),
         else => return,
     }
 }
@@ -6444,6 +6444,7 @@ fn zirIntToEnum(sema: *Sema, block: *Block, inst: Zir.Inst.Index) CompileError!A
     if (dest_ty.zigTypeTag() != .Enum) {
         return sema.fail(block, dest_ty_src, "expected enum, found '{}'", .{dest_ty.fmt(sema.mod)});
     }
+    _ = try sema.checkIntType(block, operand_src, sema.typeOf(operand));
 
     if (try sema.resolveMaybeUndefVal(block, operand_src, operand)) |int_val| {
         if (dest_ty.isNonexhaustiveEnum()) {
diff --git a/test/cases/compile_errors/stage1/obj/discarding_error_value.zig b/test/cases/compile_errors/discarding_error_value.zig
similarity index 54%
rename from test/cases/compile_errors/stage1/obj/discarding_error_value.zig
rename to test/cases/compile_errors/discarding_error_value.zig
index dcfa22e8cb..f74fc4ea29 100644
--- a/test/cases/compile_errors/stage1/obj/discarding_error_value.zig
+++ b/test/cases/compile_errors/discarding_error_value.zig
@@ -6,7 +6,7 @@ fn foo() !void {
 }
 
 // error
-// backend=stage1
+// backend=stage2
 // target=native
 //
-// tmp.zig:2:12: error: error is discarded. consider using `try`, `catch`, or `if`
+// :2:12: error: error is discarded. consider using `try`, `catch`, or `if`
diff --git a/test/cases/compile_errors/stage1/obj/duplicate_enum_field.zig b/test/cases/compile_errors/duplicate_enum_field.zig
similarity index 56%
rename from test/cases/compile_errors/stage1/obj/duplicate_enum_field.zig
rename to test/cases/compile_errors/duplicate_enum_field.zig
index cd024270bd..ebf01f99a7 100644
--- a/test/cases/compile_errors/stage1/obj/duplicate_enum_field.zig
+++ b/test/cases/compile_errors/duplicate_enum_field.zig
@@ -9,8 +9,8 @@ export fn entry() void {
 }
 
 // error
-// backend=stage1
+// backend=stage2
 // target=native
 //
-// tmp.zig:3:5: error: duplicate enum field: 'Bar'
-// tmp.zig:2:5: note: other field here
+// :3:5: error: duplicate enum field 'Bar'
+// :2:5: note: other field here
diff --git a/test/cases/compile_errors/stage1/obj/duplicate_error_in_switch.zig b/test/cases/compile_errors/duplicate_error_in_switch.zig
similarity index 65%
rename from test/cases/compile_errors/stage1/obj/duplicate_error_in_switch.zig
rename to test/cases/compile_errors/duplicate_error_in_switch.zig
index 140a14ec81..6e9b1e9099 100644
--- a/test/cases/compile_errors/stage1/obj/duplicate_error_in_switch.zig
+++ b/test/cases/compile_errors/duplicate_error_in_switch.zig
@@ -15,8 +15,8 @@ fn foo(x: i32) !void {
 }
 
 // error
-// backend=stage1
+// backend=llvm
 // target=native
 //
-// tmp.zig:5:14: error: duplicate switch value: '@typeInfo(@typeInfo(@TypeOf(foo)).Fn.return_type.?).ErrorUnion.error_set.Foo'
-// tmp.zig:3:14: note: other value here
+// :5:9: error: duplicate switch value
+// :3:9: note: other value here
diff --git a/test/cases/compile_errors/stage1/obj/explicitly_casting_non_tag_type_to_enum.zig b/test/cases/compile_errors/explicitly_casting_non_tag_type_to_enum.zig
similarity index 71%
rename from test/cases/compile_errors/stage1/obj/explicitly_casting_non_tag_type_to_enum.zig
rename to test/cases/compile_errors/explicitly_casting_non_tag_type_to_enum.zig
index 1999fd70a7..aac876e614 100644
--- a/test/cases/compile_errors/stage1/obj/explicitly_casting_non_tag_type_to_enum.zig
+++ b/test/cases/compile_errors/explicitly_casting_non_tag_type_to_enum.zig
@@ -12,7 +12,7 @@ export fn entry() void {
 }
 
 // error
-// backend=stage1
+// backend=stage2
 // target=native
 //
-// tmp.zig:10:31: error: expected integer type, found 'f32'
+// :10:31: error: expected integer type, found 'f32'
diff --git a/test/stage2/cbe.zig b/test/stage2/cbe.zig
index f602c49885..4817f0502f 100644
--- a/test/stage2/cbe.zig
+++ b/test/stage2/cbe.zig
@@ -729,8 +729,8 @@ pub fn addCases(ctx: *TestContext) !void {
             \\    _ = E1.a;
             \\}
         , &.{
-            ":1:28: error: duplicate enum tag",
-            ":1:22: note: other tag here",
+            ":1:28: error: duplicate enum field 'b'",
+            ":1:22: note: other field here",
         });
 
         case.addError(

From a6bf8c2593ae6e60d4c4804d4e9fd87fe29885ed Mon Sep 17 00:00:00 2001
From: Veikka Tuominen <git@vexu.eu>
Date: Thu, 30 Jun 2022 22:57:20 +0300
Subject: [PATCH 6/7] Sema: add more validation to zirFieldParentPtr

---
 src/Sema.zig                                  | 52 ++++++++++++++-----
 .../{stage1/obj => }/division_by_zero.zig     | 11 ++--
 .../obj => }/error_not_handled_in_switch.zig  |  7 +--
 ...comptime_field_ptr_not_based_on_struct.zig |  4 +-
 ...ldParentPtr-comptime_wrong_field_index.zig |  5 +-
 ...ParentPtr-field_pointer_is_not_pointer.zig |  4 +-
 .../obj => }/field_access_of_opaque_type.zig  |  4 +-
 .../obj => }/field_access_of_slices.zig       |  5 +-
 ...field_access_of_unknown_length_pointer.zig |  4 +-
 ...uality_but_sets_have_no_common_members.zig |  0
 10 files changed, 61 insertions(+), 35 deletions(-)
 rename test/cases/compile_errors/{stage1/obj => }/division_by_zero.zig (55%)
 rename test/cases/compile_errors/{stage1/obj => }/error_not_handled_in_switch.zig (64%)
 rename test/cases/compile_errors/{stage1/obj => }/fieldParentPtr-comptime_field_ptr_not_based_on_struct.zig (76%)
 rename test/cases/compile_errors/{stage1/obj => }/fieldParentPtr-comptime_wrong_field_index.zig (59%)
 rename test/cases/compile_errors/{stage1/obj => }/fieldParentPtr-field_pointer_is_not_pointer.zig (66%)
 rename test/cases/compile_errors/{stage1/obj => }/field_access_of_opaque_type.zig (68%)
 rename test/cases/compile_errors/{stage1/obj => }/field_access_of_slices.zig (54%)
 rename test/cases/compile_errors/{stage1/obj => }/field_access_of_unknown_length_pointer.zig (60%)
 rename test/cases/compile_errors/stage1/{obj => }/error_equality_but_sets_have_no_common_members.zig (100%)

diff --git a/src/Sema.zig b/src/Sema.zig
index 64db6a9bed..5010d86c9a 100644
--- a/src/Sema.zig
+++ b/src/Sema.zig
@@ -8378,19 +8378,15 @@ fn zirSwitchBlock(sema: *Sema, block: *Block, inst: Zir.Inst.Index) CompileError
                             block,
                             src,
                             msg,
-                            "unhandled error value: error.{s}",
+                            "unhandled error value: 'error.{s}'",
                             .{error_name},
                         );
                     }
                 }
 
                 if (maybe_msg) |msg| {
-                    try sema.mod.errNoteNonLazy(
-                        operand_ty.declSrcLoc(sema.mod),
-                        msg,
-                        "error set '{}' declared here",
-                        .{operand_ty.fmt(sema.mod)},
-                    );
+                    maybe_msg = null;
+                    try sema.addDeclaredHereNote(msg, operand_ty);
                     return sema.failWithOwnedErrorMsg(block, msg);
                 }
 
@@ -17143,9 +17139,7 @@ fn zirFieldParentPtr(sema: *Sema, block: *Block, inst: Zir.Inst.Index) CompileEr
     const field_index = struct_obj.fields.getIndex(field_name) orelse
         return sema.failWithBadStructFieldAccess(block, struct_obj, name_src, field_name);
 
-    if (field_ptr_ty.zigTypeTag() != .Pointer) {
-        return sema.fail(block, ty_src, "expected pointer type, found '{}'", .{field_ptr_ty.fmt(sema.mod)});
-    }
+    try sema.checkPtrOperand(block, ptr_src, field_ptr_ty);
     const field = struct_obj.fields.values()[field_index];
     const field_ptr_ty_info = field_ptr_ty.ptrInfo().data;
 
@@ -17168,8 +17162,29 @@ fn zirFieldParentPtr(sema: *Sema, block: *Block, inst: Zir.Inst.Index) CompileEr
     const result_ptr = try Type.ptr(sema.arena, sema.mod, ptr_ty_data);
 
     if (try sema.resolveDefinedValue(block, src, casted_field_ptr)) |field_ptr_val| {
-        const payload = field_ptr_val.castTag(.field_ptr).?.data;
-        return sema.addConstant(result_ptr, payload.container_ptr);
+        const payload = field_ptr_val.castTag(.field_ptr) orelse {
+            return sema.fail(block, ptr_src, "pointer value not based on parent struct", .{});
+        };
+        if (payload.data.field_index != field_index) {
+            const msg = msg: {
+                const msg = try sema.errMsg(
+                    block,
+                    src,
+                    "field '{s}' has index '{d}' but pointer value is index '{d}' of struct '{}'",
+                    .{
+                        field_name,
+                        field_index,
+                        payload.data.field_index,
+                        struct_ty.fmt(sema.mod),
+                    },
+                );
+                errdefer msg.destroy(sema.gpa);
+                try sema.addDeclaredHereNote(msg, struct_ty);
+                break :msg msg;
+            };
+            return sema.failWithOwnedErrorMsg(block, msg);
+        }
+        return sema.addConstant(result_ptr, payload.data.container_ptr);
     }
 
     try sema.requireRuntimeBlock(block, src);
@@ -18515,7 +18530,16 @@ fn fieldVal(
                         kw_name, child_type.fmt(sema.mod), field_name,
                     });
                 },
-                else => return sema.fail(block, src, "type '{}' has no members", .{child_type.fmt(sema.mod)}),
+                else => {
+                    const msg = msg: {
+                        const msg = try sema.errMsg(block, src, "type '{}' has no members", .{child_type.fmt(sema.mod)});
+                        errdefer msg.destroy(sema.gpa);
+                        if (child_type.isSlice()) try sema.errNote(block, src, msg, "slice values have 'len' and 'ptr' members", .{});
+                        if (child_type.zigTypeTag() == .Array) try sema.errNote(block, src, msg, "array values have 'len' member", .{});
+                        break :msg msg;
+                    };
+                    return sema.failWithOwnedErrorMsg(block, msg);
+                },
             }
         },
         .Struct => if (is_pointer_to) {
@@ -18739,7 +18763,7 @@ fn fieldPtr(
         },
         else => {},
     }
-    return sema.fail(block, src, "type '{}' does not support field access (fieldPtr, {}.{s})", .{ object_ty.fmt(sema.mod), object_ptr_ty.fmt(sema.mod), field_name });
+    return sema.fail(block, src, "type '{}' does not support field access", .{object_ty.fmt(sema.mod)});
 }
 
 fn fieldCallBind(
diff --git a/test/cases/compile_errors/stage1/obj/division_by_zero.zig b/test/cases/compile_errors/division_by_zero.zig
similarity index 55%
rename from test/cases/compile_errors/stage1/obj/division_by_zero.zig
rename to test/cases/compile_errors/division_by_zero.zig
index 3023f0c6f3..2e2f7e2be2 100644
--- a/test/cases/compile_errors/stage1/obj/division_by_zero.zig
+++ b/test/cases/compile_errors/division_by_zero.zig
@@ -6,13 +6,12 @@ const float_x = @as(f32, 1.0) / @as(f32, 0.0);
 export fn entry1() usize { return @sizeOf(@TypeOf(lit_int_x)); }
 export fn entry2() usize { return @sizeOf(@TypeOf(lit_float_x)); }
 export fn entry3() usize { return @sizeOf(@TypeOf(int_x)); }
-export fn entry4() usize { return @sizeOf(@TypeOf(float_x)); }
+export fn entry4() usize { return @sizeOf(@TypeOf(float_x)); } // no error on purpose
 
 // error
-// backend=stage1
+// backend=stage2
 // target=native
 //
-// tmp.zig:1:21: error: division by zero
-// tmp.zig:2:25: error: division by zero
-// tmp.zig:3:27: error: division by zero
-// tmp.zig:4:31: error: division by zero
+// :1:23: error: division by zero here causes undefined behavior
+// :2:27: error: division by zero here causes undefined behavior
+// :3:29: error: division by zero here causes undefined behavior
diff --git a/test/cases/compile_errors/stage1/obj/error_not_handled_in_switch.zig b/test/cases/compile_errors/error_not_handled_in_switch.zig
similarity index 64%
rename from test/cases/compile_errors/stage1/obj/error_not_handled_in_switch.zig
rename to test/cases/compile_errors/error_not_handled_in_switch.zig
index 12ee35daef..8f0d26a4a9 100644
--- a/test/cases/compile_errors/stage1/obj/error_not_handled_in_switch.zig
+++ b/test/cases/compile_errors/error_not_handled_in_switch.zig
@@ -13,8 +13,9 @@ fn foo(x: i32) !void {
 }
 
 // error
-// backend=stage1
+// backend=llvm
 // target=native
 //
-// tmp.zig:2:26: error: error.Baz not handled in switch
-// tmp.zig:2:26: error: error.Bar not handled in switch
+// :2:26: error: switch must handle all possibilities
+// :2:26: note: unhandled error value: 'error.Bar'
+// :2:26: note: unhandled error value: 'error.Baz'
diff --git a/test/cases/compile_errors/stage1/obj/fieldParentPtr-comptime_field_ptr_not_based_on_struct.zig b/test/cases/compile_errors/fieldParentPtr-comptime_field_ptr_not_based_on_struct.zig
similarity index 76%
rename from test/cases/compile_errors/stage1/obj/fieldParentPtr-comptime_field_ptr_not_based_on_struct.zig
rename to test/cases/compile_errors/fieldParentPtr-comptime_field_ptr_not_based_on_struct.zig
index 9375f4639a..7f57268f06 100644
--- a/test/cases/compile_errors/stage1/obj/fieldParentPtr-comptime_field_ptr_not_based_on_struct.zig
+++ b/test/cases/compile_errors/fieldParentPtr-comptime_field_ptr_not_based_on_struct.zig
@@ -11,7 +11,7 @@ comptime {
 }
 
 // error
-// backend=stage1
+// backend=stage2
 // target=native
 //
-// tmp.zig:9:55: error: pointer value not based on parent struct
+// :9:55: error: pointer value not based on parent struct
diff --git a/test/cases/compile_errors/stage1/obj/fieldParentPtr-comptime_wrong_field_index.zig b/test/cases/compile_errors/fieldParentPtr-comptime_wrong_field_index.zig
similarity index 59%
rename from test/cases/compile_errors/stage1/obj/fieldParentPtr-comptime_wrong_field_index.zig
rename to test/cases/compile_errors/fieldParentPtr-comptime_wrong_field_index.zig
index c322543dc0..a73409aea3 100644
--- a/test/cases/compile_errors/stage1/obj/fieldParentPtr-comptime_wrong_field_index.zig
+++ b/test/cases/compile_errors/fieldParentPtr-comptime_wrong_field_index.zig
@@ -10,7 +10,8 @@ comptime {
 }
 
 // error
-// backend=stage1
+// backend=stage2
 // target=native
 //
-// tmp.zig:8:29: error: field 'b' has index 1 but pointer value is index 0 of struct 'Foo'
+// :8:29: error: field 'b' has index '1' but pointer value is index '0' of struct 'tmp.Foo'
+// :1:13: note: struct declared here
diff --git a/test/cases/compile_errors/stage1/obj/fieldParentPtr-field_pointer_is_not_pointer.zig b/test/cases/compile_errors/fieldParentPtr-field_pointer_is_not_pointer.zig
similarity index 66%
rename from test/cases/compile_errors/stage1/obj/fieldParentPtr-field_pointer_is_not_pointer.zig
rename to test/cases/compile_errors/fieldParentPtr-field_pointer_is_not_pointer.zig
index 71360e5681..8a57d08c3b 100644
--- a/test/cases/compile_errors/stage1/obj/fieldParentPtr-field_pointer_is_not_pointer.zig
+++ b/test/cases/compile_errors/fieldParentPtr-field_pointer_is_not_pointer.zig
@@ -6,7 +6,7 @@ export fn foo(a: i32) *Foo {
 }
 
 // error
-// backend=stage1
+// backend=stage2
 // target=native
 //
-// tmp.zig:5:38: error: expected pointer, found 'i32'
+// :5:38: error: expected pointer type, found 'i32'
diff --git a/test/cases/compile_errors/stage1/obj/field_access_of_opaque_type.zig b/test/cases/compile_errors/field_access_of_opaque_type.zig
similarity index 68%
rename from test/cases/compile_errors/stage1/obj/field_access_of_opaque_type.zig
rename to test/cases/compile_errors/field_access_of_opaque_type.zig
index 963c89dafe..f9ec483305 100644
--- a/test/cases/compile_errors/stage1/obj/field_access_of_opaque_type.zig
+++ b/test/cases/compile_errors/field_access_of_opaque_type.zig
@@ -10,7 +10,7 @@ fn bar(x: *MyType) bool {
 }
 
 // error
-// backend=stage1
+// backend=stage2
 // target=native
 //
-// tmp.zig:9:13: error: no member named 'blah' in opaque type 'MyType'
+// :9:13: error: type '*tmp.MyType' does not support field access
diff --git a/test/cases/compile_errors/stage1/obj/field_access_of_slices.zig b/test/cases/compile_errors/field_access_of_slices.zig
similarity index 54%
rename from test/cases/compile_errors/stage1/obj/field_access_of_slices.zig
rename to test/cases/compile_errors/field_access_of_slices.zig
index 45ca711367..1fbfda9646 100644
--- a/test/cases/compile_errors/stage1/obj/field_access_of_slices.zig
+++ b/test/cases/compile_errors/field_access_of_slices.zig
@@ -5,7 +5,8 @@ export fn entry() void {
 }
 
 // error
-// backend=stage1
+// backend=stage2
 // target=native
 //
-// tmp.zig:3:32: error: type 'type' does not support field access
+// :3:32: error: type '[]i32' has no members
+// :3:32: note: slice values have 'len' and 'ptr' members
diff --git a/test/cases/compile_errors/stage1/obj/field_access_of_unknown_length_pointer.zig b/test/cases/compile_errors/field_access_of_unknown_length_pointer.zig
similarity index 60%
rename from test/cases/compile_errors/stage1/obj/field_access_of_unknown_length_pointer.zig
rename to test/cases/compile_errors/field_access_of_unknown_length_pointer.zig
index f9a37cabcc..2f526277fe 100644
--- a/test/cases/compile_errors/stage1/obj/field_access_of_unknown_length_pointer.zig
+++ b/test/cases/compile_errors/field_access_of_unknown_length_pointer.zig
@@ -7,7 +7,7 @@ export fn entry(foo: [*]Foo) void {
 }
 
 // error
-// backend=stage1
+// backend=stage2
 // target=native
 //
-// tmp.zig:6:8: error: type '[*]Foo' does not support field access
+// :6:8: error: type '[*]tmp.Foo' does not support field access
diff --git a/test/cases/compile_errors/stage1/obj/error_equality_but_sets_have_no_common_members.zig b/test/cases/compile_errors/stage1/error_equality_but_sets_have_no_common_members.zig
similarity index 100%
rename from test/cases/compile_errors/stage1/obj/error_equality_but_sets_have_no_common_members.zig
rename to test/cases/compile_errors/stage1/error_equality_but_sets_have_no_common_members.zig

From 2029601cb2ad4a6e9c8b260eec68de881d46735b Mon Sep 17 00:00:00 2001
From: Veikka Tuominen <git@vexu.eu>
Date: Thu, 30 Jun 2022 23:59:39 +0300
Subject: [PATCH 7/7] AstGen: use elem_{ptr,val}_node for array access syntax

---
 src/AstGen.zig                                | 25 ++++++------
 src/Sema.zig                                  | 39 ++++++++++---------
 src/Zir.zig                                   | 19 +++++----
 src/print_zir.zig                             |  4 +-
 src/type.zig                                  |  2 +-
 .../ignored_deferred_function_call.zig        |  4 +-
 ...nored_expression_in_while_continuation.zig |  8 ++--
 .../illegal_comparison_of_types.zig           | 20 ++++++++++
 .../implicitly_casting_enum_to_tag_type.zig   |  4 +-
 .../obj => }/incorrect_return_type.zig        |  4 +-
 .../indexing_an_array_of_size_zero.zig        |  4 +-
 ..._array_of_size_zero_with_runtime_index.zig |  4 +-
 .../obj => }/indexing_single-item_pointer.zig |  4 +-
 ...nvalid_cast_from_integral_type_to_enum.zig |  4 +-
 .../runtime_indexing_comptime_array.zig       | 12 +++---
 .../implicit_cast_from_f64_to_f32.zig         |  0
 .../stage1/{obj => }/int_to_ptr_of_0_bits.zig |  0
 .../obj/illegal_comparison_of_types.zig       | 20 ----------
 18 files changed, 90 insertions(+), 87 deletions(-)
 rename test/cases/compile_errors/{stage1/obj => }/ignored_deferred_function_call.zig (52%)
 rename test/cases/compile_errors/{stage1/obj => }/ignored_expression_in_while_continuation.zig (54%)
 create mode 100644 test/cases/compile_errors/illegal_comparison_of_types.zig
 rename test/cases/compile_errors/{stage1/obj => }/implicitly_casting_enum_to_tag_type.zig (68%)
 rename test/cases/compile_errors/{stage1/obj => }/incorrect_return_type.zig (75%)
 rename test/cases/compile_errors/{stage1/obj => }/indexing_an_array_of_size_zero.zig (59%)
 rename test/cases/compile_errors/{stage1/obj => }/indexing_an_array_of_size_zero_with_runtime_index.zig (64%)
 rename test/cases/compile_errors/{stage1/obj => }/indexing_single-item_pointer.zig (51%)
 rename test/cases/compile_errors/{stage1/obj => }/invalid_cast_from_integral_type_to_enum.zig (70%)
 rename test/cases/compile_errors/stage1/{obj => }/implicit_cast_from_f64_to_f32.zig (100%)
 rename test/cases/compile_errors/stage1/{obj => }/int_to_ptr_of_0_bits.zig (100%)
 delete mode 100644 test/cases/compile_errors/stage1/obj/illegal_comparison_of_types.zig

diff --git a/src/AstGen.zig b/src/AstGen.zig
index 8707728313..a0ff7a0e6e 100644
--- a/src/AstGen.zig
+++ b/src/AstGen.zig
@@ -5154,16 +5154,14 @@ fn arrayAccess(
     const tree = astgen.tree;
     const node_datas = tree.nodes.items(.data);
     switch (rl) {
-        .ref => return gz.addBin(
-            .elem_ptr,
-            try expr(gz, scope, .ref, node_datas[node].lhs),
-            try expr(gz, scope, .{ .ty = .usize_type }, node_datas[node].rhs),
-        ),
-        else => return rvalue(gz, rl, try gz.addBin(
-            .elem_val,
-            try expr(gz, scope, .none, node_datas[node].lhs),
-            try expr(gz, scope, .{ .coerced_ty = .usize_type }, node_datas[node].rhs),
-        ), node),
+        .ref => return gz.addPlNode(.elem_ptr_node, node, Zir.Inst.Bin{
+            .lhs = try expr(gz, scope, .ref, node_datas[node].lhs),
+            .rhs = try expr(gz, scope, .{ .ty = .usize_type }, node_datas[node].rhs),
+        }),
+        else => return rvalue(gz, rl, try gz.addPlNode(.elem_val_node, node, Zir.Inst.Bin{
+            .lhs = try expr(gz, scope, .none, node_datas[node].lhs),
+            .rhs = try expr(gz, scope, .{ .ty = .usize_type }, node_datas[node].rhs),
+        }), node),
     }
 }
 
@@ -5685,7 +5683,7 @@ fn whileExpr(
         try then_scope.addDbgVar(.dbg_var_val, some, dbg_var_inst);
     }
     if (while_full.ast.cont_expr != 0) {
-        _ = try expr(&loop_scope, then_sub_scope, .{ .ty = .void_type }, while_full.ast.cont_expr);
+        _ = try unusedResultExpr(&loop_scope, then_sub_scope, while_full.ast.cont_expr);
     }
     try then_scope.addDbgBlockEnd();
     const repeat_tag: Zir.Inst.Tag = if (is_inline) .repeat_inline else .repeat;
@@ -5890,7 +5888,10 @@ fn forExpr(
         if (!mem.eql(u8, value_name, "_")) {
             const name_str_index = try astgen.identAsString(ident);
             const tag: Zir.Inst.Tag = if (is_ptr) .elem_ptr else .elem_val;
-            const payload_inst = try then_scope.addBin(tag, array_ptr, index);
+            const payload_inst = try then_scope.addPlNode(tag, for_full.ast.cond_expr, Zir.Inst.Bin{
+                .lhs = array_ptr,
+                .rhs = index,
+            });
             try astgen.detectLocalShadowing(&then_scope.base, name_str_index, ident, value_name);
             payload_val_scope = .{
                 .parent = &then_scope.base,
diff --git a/src/Sema.zig b/src/Sema.zig
index 5010d86c9a..b946e29057 100644
--- a/src/Sema.zig
+++ b/src/Sema.zig
@@ -2738,6 +2738,7 @@ fn ensureResultUsed(
     const operand_ty = sema.typeOf(operand);
     switch (operand_ty.zigTypeTag()) {
         .Void, .NoReturn => return,
+        .ErrorSet, .ErrorUnion => return sema.fail(block, src, "error is ignored. consider using `try`, `catch`, or `if`", .{}),
         else => return sema.fail(block, src, "expression value is ignored", .{}),
     }
 }
@@ -2751,7 +2752,7 @@ fn zirEnsureResultNonError(sema: *Sema, block: *Block, inst: Zir.Inst.Index) Com
     const src = inst_data.src();
     const operand_ty = sema.typeOf(operand);
     switch (operand_ty.zigTypeTag()) {
-        .ErrorSet, .ErrorUnion => return sema.fail(block, src, "error is discardederror is discarded. consider using `try`, `catch`, or `if`", .{}),
+        .ErrorSet, .ErrorUnion => return sema.fail(block, src, "error is discarded. consider using `try`, `catch`, or `if`", .{}),
         else => return,
     }
 }
@@ -7092,7 +7093,7 @@ fn funcCommon(
         const param_types = try sema.arena.alloc(Type, block.params.items.len);
         const comptime_params = try sema.arena.alloc(bool, block.params.items.len);
         for (block.params.items) |param, i| {
-            const param_src = LazySrcLoc.nodeOffset(src_node_offset); // TODO better src
+            const param_src = LazySrcLoc.nodeOffset(src_node_offset); // TODO better soruce location
             param_types[i] = param.ty;
             comptime_params[i] = param.is_comptime or
                 try sema.typeRequiresComptime(block, param_src, param.ty);
@@ -7798,12 +7799,12 @@ fn zirElemVal(sema: *Sema, block: *Block, inst: Zir.Inst.Index) CompileError!Air
     const tracy = trace(@src());
     defer tracy.end();
 
-    const bin_inst = sema.code.instructions.items(.data)[inst].bin;
-    const src = sema.src; // TODO better source location
-    const elem_index_src = sema.src; // TODO better source location
-    const array = try sema.resolveInst(bin_inst.lhs);
-    const elem_index = try sema.resolveInst(bin_inst.rhs);
-    return sema.elemVal(block, src, array, elem_index, elem_index_src);
+    const inst_data = sema.code.instructions.items(.data)[inst].pl_node;
+    const src = inst_data.src();
+    const extra = sema.code.extraData(Zir.Inst.Bin, inst_data.payload_index).data;
+    const array = try sema.resolveInst(extra.lhs);
+    const elem_index = try sema.resolveInst(extra.rhs);
+    return sema.elemVal(block, src, array, elem_index, src);
 }
 
 fn zirElemValNode(sema: *Sema, block: *Block, inst: Zir.Inst.Index) CompileError!Air.Inst.Ref {
@@ -7823,10 +7824,12 @@ fn zirElemPtr(sema: *Sema, block: *Block, inst: Zir.Inst.Index) CompileError!Air
     const tracy = trace(@src());
     defer tracy.end();
 
-    const bin_inst = sema.code.instructions.items(.data)[inst].bin;
-    const array_ptr = try sema.resolveInst(bin_inst.lhs);
-    const elem_index = try sema.resolveInst(bin_inst.rhs);
-    return sema.elemPtr(block, sema.src, array_ptr, elem_index, sema.src, false);
+    const inst_data = sema.code.instructions.items(.data)[inst].pl_node;
+    const src = inst_data.src();
+    const extra = sema.code.extraData(Zir.Inst.Bin, inst_data.payload_index).data;
+    const array_ptr = try sema.resolveInst(extra.lhs);
+    const elem_index = try sema.resolveInst(extra.rhs);
+    return sema.elemPtr(block, src, array_ptr, elem_index, src, false);
 }
 
 fn zirElemPtrNode(sema: *Sema, block: *Block, inst: Zir.Inst.Index) CompileError!Air.Inst.Ref {
@@ -19454,7 +19457,7 @@ fn tupleFieldPtr(
     const tuple_fields = tuple_ty.tupleFields();
 
     if (tuple_fields.types.len == 0) {
-        return sema.fail(block, field_index_src, "indexing into empty tuple", .{});
+        return sema.fail(block, tuple_ptr_src, "indexing into empty tuple is not allowed", .{});
     }
 
     if (field_index >= tuple_fields.types.len) {
@@ -19497,7 +19500,7 @@ fn tupleField(
     const tuple_fields = tuple_ty.tupleFields();
 
     if (tuple_fields.types.len == 0) {
-        return sema.fail(block, field_index_src, "indexing into empty tuple", .{});
+        return sema.fail(block, tuple_src, "indexing into empty tuple is not allowed", .{});
     }
 
     if (field_index >= tuple_fields.types.len) {
@@ -19538,7 +19541,7 @@ fn elemValArray(
     const elem_ty = array_ty.childType();
 
     if (array_len_s == 0) {
-        return sema.fail(block, elem_index_src, "indexing into empty array", .{});
+        return sema.fail(block, array_src, "indexing into empty array is not allowed", .{});
     }
 
     const maybe_undef_array_val = try sema.resolveMaybeUndefVal(block, array_src, array);
@@ -19618,7 +19621,7 @@ fn elemPtrArray(
     const array_len_s = array_len + @boolToInt(array_sent);
 
     if (array_len_s == 0) {
-        return sema.fail(block, elem_index_src, "indexing into empty array", .{});
+        return sema.fail(block, array_ptr_src, "indexing into empty array is not allowed", .{});
     }
 
     const maybe_undef_array_ptr_val = try sema.resolveMaybeUndefVal(block, array_ptr_src, array_ptr);
@@ -19700,7 +19703,7 @@ fn elemValSlice(
         const slice_len = slice_val.sliceLen(sema.mod);
         const slice_len_s = slice_len + @boolToInt(slice_sent);
         if (slice_len_s == 0) {
-            return sema.fail(block, elem_index_src, "indexing into empty slice", .{});
+            return sema.fail(block, slice_src, "indexing into empty slice is not allowed", .{});
         }
         if (maybe_index_val) |index_val| {
             const index = @intCast(usize, index_val.toUnsignedInt(target));
@@ -19757,7 +19760,7 @@ fn elemPtrSlice(
         const slice_len = slice_val.sliceLen(sema.mod);
         const slice_len_s = slice_len + @boolToInt(slice_sent);
         if (slice_len_s == 0) {
-            return sema.fail(block, elem_index_src, "indexing into empty slice", .{});
+            return sema.fail(block, slice_src, "indexing into empty slice is not allowed", .{});
         }
         if (offset) |index| {
             if (index >= slice_len_s) {
diff --git a/src/Zir.zig b/src/Zir.zig
index 26bb09860d..98cdd490b8 100644
--- a/src/Zir.zig
+++ b/src/Zir.zig
@@ -370,24 +370,23 @@ pub const Inst = struct {
         /// Uses the `pl_node` union field. Payload is `Bin`.
         div,
         /// Given a pointer to an array, slice, or pointer, returns a pointer to the element at
-        /// the provided index. Uses the `bin` union field. Source location is implied
-        /// to be the same as the previous instruction.
-        elem_ptr,
-        /// Same as `elem_ptr` except also stores a source location node.
+        /// the provided index.
         /// Uses the `pl_node` union field. AST node is a[b] syntax. Payload is `Bin`.
         elem_ptr_node,
+        /// Same as `elem_ptr_node` but used only for for loop.
+        /// Uses the `pl_node` union field. AST node is the condition of a for loop. Payload is `Bin`.
+        elem_ptr,
         /// Same as `elem_ptr_node` except the index is stored immediately rather than
         /// as a reference to another ZIR instruction.
         /// Uses the `pl_node` union field. AST node is an element inside array initialization
         /// syntax. Payload is `ElemPtrImm`.
         elem_ptr_imm,
         /// Given an array, slice, or pointer, returns the element at the provided index.
-        /// Uses the `bin` union field. Source location is implied to be the same
-        /// as the previous instruction.
-        elem_val,
-        /// Same as `elem_val` except also stores a source location node.
         /// Uses the `pl_node` union field. AST node is a[b] syntax. Payload is `Bin`.
         elem_val_node,
+        /// Same as `elem_val_node` but used only for for loop.
+        /// Uses the `pl_node` union field. AST node is the condition of a for loop. Payload is `Bin`.
+        elem_val,
         /// Emits a compile error if the operand is not `void`.
         /// Uses the `un_node` field.
         ensure_result_used,
@@ -1627,10 +1626,10 @@ pub const Inst = struct {
                 .decl_val = .str_tok,
                 .load = .un_node,
                 .div = .pl_node,
-                .elem_ptr = .bin,
+                .elem_ptr = .pl_node,
                 .elem_ptr_node = .pl_node,
                 .elem_ptr_imm = .pl_node,
-                .elem_val = .bin,
+                .elem_val = .pl_node,
                 .elem_val_node = .pl_node,
                 .ensure_result_used = .un_node,
                 .ensure_result_non_error = .un_node,
diff --git a/src/print_zir.zig b/src/print_zir.zig
index fe8446b34a..b19076a7f0 100644
--- a/src/print_zir.zig
+++ b/src/print_zir.zig
@@ -144,8 +144,6 @@ const Writer = struct {
         switch (tag) {
             .array_type,
             .as,
-            .elem_ptr,
-            .elem_val,
             .store,
             .store_to_block_ptr,
             .store_to_inferred_ptr,
@@ -355,6 +353,8 @@ const Writer = struct {
             .minimum,
             .elem_ptr_node,
             .elem_val_node,
+            .elem_ptr,
+            .elem_val,
             .coerce_result_ptr,
             => try self.writePlNodeBin(stream, inst),
 
diff --git a/src/type.zig b/src/type.zig
index 0ca7ba83c5..50302dca6c 100644
--- a/src/type.zig
+++ b/src/type.zig
@@ -189,7 +189,7 @@ pub const Type = extern union {
             .Frame,
             => false,
 
-            .Pointer => is_equality_cmp or ty.isCPtr(),
+            .Pointer => !ty.isSlice() and (is_equality_cmp or ty.isCPtr()),
             .Optional => {
                 if (!is_equality_cmp) return false;
                 var buf: Payload.ElemType = undefined;
diff --git a/test/cases/compile_errors/stage1/obj/ignored_deferred_function_call.zig b/test/cases/compile_errors/ignored_deferred_function_call.zig
similarity index 52%
rename from test/cases/compile_errors/stage1/obj/ignored_deferred_function_call.zig
rename to test/cases/compile_errors/ignored_deferred_function_call.zig
index 41812bfda9..69df8b0498 100644
--- a/test/cases/compile_errors/stage1/obj/ignored_deferred_function_call.zig
+++ b/test/cases/compile_errors/ignored_deferred_function_call.zig
@@ -4,7 +4,7 @@ export fn foo() void {
 fn bar() anyerror!i32 { return 0; }
 
 // error
-// backend=stage1
+// backend=stage2
 // target=native
 //
-// tmp.zig:2:14: error: error is ignored. consider using `try`, `catch`, or `if`
+// :2:14: error: error is ignored. consider using `try`, `catch`, or `if`
diff --git a/test/cases/compile_errors/stage1/obj/ignored_expression_in_while_continuation.zig b/test/cases/compile_errors/ignored_expression_in_while_continuation.zig
similarity index 54%
rename from test/cases/compile_errors/stage1/obj/ignored_expression_in_while_continuation.zig
rename to test/cases/compile_errors/ignored_expression_in_while_continuation.zig
index 43f3713fc6..d295d476ab 100644
--- a/test/cases/compile_errors/stage1/obj/ignored_expression_in_while_continuation.zig
+++ b/test/cases/compile_errors/ignored_expression_in_while_continuation.zig
@@ -14,9 +14,9 @@ fn bad() anyerror!void {
 }
 
 // error
-// backend=stage1
+// backend=stage2
 // target=native
 //
-// tmp.zig:2:24: error: error is ignored. consider using `try`, `catch`, or `if`
-// tmp.zig:6:25: error: error is ignored. consider using `try`, `catch`, or `if`
-// tmp.zig:10:25: error: error is ignored. consider using `try`, `catch`, or `if`
+// :2:24: error: error is ignored. consider using `try`, `catch`, or `if`
+// :6:25: error: error is ignored. consider using `try`, `catch`, or `if`
+// :10:25: error: error is ignored. consider using `try`, `catch`, or `if`
diff --git a/test/cases/compile_errors/illegal_comparison_of_types.zig b/test/cases/compile_errors/illegal_comparison_of_types.zig
new file mode 100644
index 0000000000..69d7a28fa4
--- /dev/null
+++ b/test/cases/compile_errors/illegal_comparison_of_types.zig
@@ -0,0 +1,20 @@
+fn bad_eql_1(a: []u8, b: []u8) bool {
+    return a == b;
+}
+const EnumWithData = union(enum) {
+    One: void,
+    Two: i32,
+};
+fn bad_eql_2(a: *const EnumWithData, b: *const EnumWithData) bool {
+    return a.* == b.*;
+}
+
+export fn entry1() usize { return @sizeOf(@TypeOf(&bad_eql_1)); }
+export fn entry2() usize { return @sizeOf(@TypeOf(&bad_eql_2)); }
+
+// error
+// backend=stage2
+// target=native
+//
+// :2:14: error: operator == not allowed for type '[]u8'
+// :9:16: error: operator == not allowed for type 'tmp.EnumWithData'
diff --git a/test/cases/compile_errors/stage1/obj/implicitly_casting_enum_to_tag_type.zig b/test/cases/compile_errors/implicitly_casting_enum_to_tag_type.zig
similarity index 68%
rename from test/cases/compile_errors/stage1/obj/implicitly_casting_enum_to_tag_type.zig
rename to test/cases/compile_errors/implicitly_casting_enum_to_tag_type.zig
index a40615f99b..b1930cb548 100644
--- a/test/cases/compile_errors/stage1/obj/implicitly_casting_enum_to_tag_type.zig
+++ b/test/cases/compile_errors/implicitly_casting_enum_to_tag_type.zig
@@ -11,7 +11,7 @@ export fn entry() void {
 }
 
 // error
-// backend=stage1
+// backend=stage2
 // target=native
 //
-// tmp.zig:9:22: error: expected type 'u2', found 'Small'
+// :9:22: error: expected type 'u2', found 'tmp.Small'
diff --git a/test/cases/compile_errors/stage1/obj/incorrect_return_type.zig b/test/cases/compile_errors/incorrect_return_type.zig
similarity index 75%
rename from test/cases/compile_errors/stage1/obj/incorrect_return_type.zig
rename to test/cases/compile_errors/incorrect_return_type.zig
index b25e2a8ea4..b37cbebc7f 100644
--- a/test/cases/compile_errors/stage1/obj/incorrect_return_type.zig
+++ b/test/cases/compile_errors/incorrect_return_type.zig
@@ -15,7 +15,7 @@
  }
 
 // error
-// backend=stage1
+// backend=stage2
 // target=native
 //
-// tmp.zig:8:16: error: expected type 'A', found 'B'
+// :8:16: error: expected type 'tmp.A', found 'tmp.B'
diff --git a/test/cases/compile_errors/stage1/obj/indexing_an_array_of_size_zero.zig b/test/cases/compile_errors/indexing_an_array_of_size_zero.zig
similarity index 59%
rename from test/cases/compile_errors/stage1/obj/indexing_an_array_of_size_zero.zig
rename to test/cases/compile_errors/indexing_an_array_of_size_zero.zig
index dfb2e7c1c3..d2a54046de 100644
--- a/test/cases/compile_errors/stage1/obj/indexing_an_array_of_size_zero.zig
+++ b/test/cases/compile_errors/indexing_an_array_of_size_zero.zig
@@ -5,7 +5,7 @@ export fn foo() void {
 }
 
 // error
-// backend=stage1
+// backend=stage2
 // target=native
 //
-// tmp.zig:3:27: error: accessing a zero length array is not allowed
+// :3:27: error: indexing into empty array is not allowed
diff --git a/test/cases/compile_errors/stage1/obj/indexing_an_array_of_size_zero_with_runtime_index.zig b/test/cases/compile_errors/indexing_an_array_of_size_zero_with_runtime_index.zig
similarity index 64%
rename from test/cases/compile_errors/stage1/obj/indexing_an_array_of_size_zero_with_runtime_index.zig
rename to test/cases/compile_errors/indexing_an_array_of_size_zero_with_runtime_index.zig
index f50931312e..eceb5db50e 100644
--- a/test/cases/compile_errors/stage1/obj/indexing_an_array_of_size_zero_with_runtime_index.zig
+++ b/test/cases/compile_errors/indexing_an_array_of_size_zero_with_runtime_index.zig
@@ -6,7 +6,7 @@ export fn foo() void {
 }
 
 // error
-// backend=stage1
+// backend=stage2
 // target=native
 //
-// tmp.zig:4:27: error: accessing a zero length array is not allowed
+// :4:27: error: indexing into empty array is not allowed
diff --git a/test/cases/compile_errors/stage1/obj/indexing_single-item_pointer.zig b/test/cases/compile_errors/indexing_single-item_pointer.zig
similarity index 51%
rename from test/cases/compile_errors/stage1/obj/indexing_single-item_pointer.zig
rename to test/cases/compile_errors/indexing_single-item_pointer.zig
index bc7951ec96..efd063817c 100644
--- a/test/cases/compile_errors/stage1/obj/indexing_single-item_pointer.zig
+++ b/test/cases/compile_errors/indexing_single-item_pointer.zig
@@ -3,7 +3,7 @@ export fn entry(ptr: *i32) i32 {
 }
 
 // error
-// backend=stage1
+// backend=stage2
 // target=native
 //
-// tmp.zig:2:15: error: index of single-item pointer
+// :2:15: error: element access of non-indexable type '*i32'
diff --git a/test/cases/compile_errors/stage1/obj/invalid_cast_from_integral_type_to_enum.zig b/test/cases/compile_errors/invalid_cast_from_integral_type_to_enum.zig
similarity index 70%
rename from test/cases/compile_errors/stage1/obj/invalid_cast_from_integral_type_to_enum.zig
rename to test/cases/compile_errors/invalid_cast_from_integral_type_to_enum.zig
index 81dbd88e3b..ce2f64169b 100644
--- a/test/cases/compile_errors/stage1/obj/invalid_cast_from_integral_type_to_enum.zig
+++ b/test/cases/compile_errors/invalid_cast_from_integral_type_to_enum.zig
@@ -11,7 +11,7 @@ fn foo(x: usize) void {
 }
 
 // error
-// backend=stage1
+// backend=stage2
 // target=native
 //
-// tmp.zig:9:10: error: expected type 'usize', found 'E'
+// :9:10: error: expected type 'usize', found 'tmp.E'
diff --git a/test/cases/compile_errors/runtime_indexing_comptime_array.zig b/test/cases/compile_errors/runtime_indexing_comptime_array.zig
index 16f7305f63..b83e977b3f 100644
--- a/test/cases/compile_errors/runtime_indexing_comptime_array.zig
+++ b/test/cases/compile_errors/runtime_indexing_comptime_array.zig
@@ -24,9 +24,9 @@ pub export fn entry3() void {
 // target=native
 // backend=stage2
 //
-// :6:5: error: values of type '[2]fn() void' must be comptime known, but index value is runtime known
-// :6:5: note: use '*const fn() void' for a function pointer type
-// :13:5: error: values of type '[2]fn() void' must be comptime known, but index value is runtime known
-// :13:5: note: use '*const fn() void' for a function pointer type
-// :19:5: error: values of type '[2]fn() void' must be comptime known, but index value is runtime known
-// :19:5: note: use '*const fn() void' for a function pointer type
+// :7:10: error: values of type '[2]fn() void' must be comptime known, but index value is runtime known
+// :7:10: note: use '*const fn() void' for a function pointer type
+// :15:18: error: values of type '[2]fn() void' must be comptime known, but index value is runtime known
+// :15:17: note: use '*const fn() void' for a function pointer type
+// :21:19: error: values of type '[2]fn() void' must be comptime known, but index value is runtime known
+// :21:18: note: use '*const fn() void' for a function pointer type
diff --git a/test/cases/compile_errors/stage1/obj/implicit_cast_from_f64_to_f32.zig b/test/cases/compile_errors/stage1/implicit_cast_from_f64_to_f32.zig
similarity index 100%
rename from test/cases/compile_errors/stage1/obj/implicit_cast_from_f64_to_f32.zig
rename to test/cases/compile_errors/stage1/implicit_cast_from_f64_to_f32.zig
diff --git a/test/cases/compile_errors/stage1/obj/int_to_ptr_of_0_bits.zig b/test/cases/compile_errors/stage1/int_to_ptr_of_0_bits.zig
similarity index 100%
rename from test/cases/compile_errors/stage1/obj/int_to_ptr_of_0_bits.zig
rename to test/cases/compile_errors/stage1/int_to_ptr_of_0_bits.zig
diff --git a/test/cases/compile_errors/stage1/obj/illegal_comparison_of_types.zig b/test/cases/compile_errors/stage1/obj/illegal_comparison_of_types.zig
deleted file mode 100644
index d04eaec3b5..0000000000
--- a/test/cases/compile_errors/stage1/obj/illegal_comparison_of_types.zig
+++ /dev/null
@@ -1,20 +0,0 @@
-fn bad_eql_1(a: []u8, b: []u8) bool {
-    return a == b;
-}
-const EnumWithData = union(enum) {
-    One: void,
-    Two: i32,
-};
-fn bad_eql_2(a: *const EnumWithData, b: *const EnumWithData) bool {
-    return a.* == b.*;
-}
-
-export fn entry1() usize { return @sizeOf(@TypeOf(bad_eql_1)); }
-export fn entry2() usize { return @sizeOf(@TypeOf(bad_eql_2)); }
-
-// error
-// backend=stage1
-// target=native
-//
-// tmp.zig:2:14: error: operator not allowed for type '[]u8'
-// tmp.zig:9:16: error: operator not allowed for type 'EnumWithData'