zig

commit 11a81e1b29ecefd7aad2ebe951743c44272e1817 (tree)
parent f24c77fc48b7272618b48cac7bb15d6997e95c5a
Author: shwqf <vvvv0932313@gmail.com>
Date:   Sun, 18 Dec 2022 10:09:35 +0800

Call ensureResultUsed before comptime .call is evaluated.

Fixes #12580

Diffstat:
M
src/Sema.zig
 | 
17
++++++++++-------
M
test/cases/compile_errors/ignored_comptime_value.zig
 | 
17
++++++++++++++++-

2 files changed, 26 insertions(+), 8 deletions(-)
diff --git a/src/Sema.zig b/src/Sema.zig
@@ -3254,17 +3254,16 @@ fn zirEnsureResultUsed(sema: *Sema, block: *Block, inst: Zir.Inst.Index) Compile
     const operand = try sema.resolveInst(inst_data.operand);
     const src = inst_data.src();
 
-    return sema.ensureResultUsed(block, operand, src);
+    return sema.ensureResultUsed(block, sema.typeOf(operand), src);
 }
 
 fn ensureResultUsed(
     sema: *Sema,
     block: *Block,
-    operand: Air.Inst.Ref,
+    ty: Type,
     src: LazySrcLoc,
 ) CompileError!void {
-    const operand_ty = sema.typeOf(operand);
-    switch (operand_ty.zigTypeTag()) {
+    switch (ty.zigTypeTag()) {
         .Void, .NoReturn => return,
         .ErrorSet, .ErrorUnion => {
             const msg = msg: {
@@ -3277,7 +3276,7 @@ fn ensureResultUsed(
         },
         else => {
             const msg = msg: {
-                const msg = try sema.errMsg(block, src, "value of type '{}' ignored", .{operand_ty.fmt(sema.mod)});
+                const msg = try sema.errMsg(block, src, "value of type '{}' ignored", .{ty.fmt(sema.mod)});
                 errdefer msg.destroy(sema.gpa);
                 try sema.errNote(block, src, msg, "all non-void values must be used", .{});
                 try sema.errNote(block, src, msg, "this error can be suppressed by assigning the value to '_'", .{});
@@ -6641,6 +6640,10 @@ fn analyzeCall(
                 };
             }
 
+            if (is_comptime_call and ensure_result_used) {
+                try sema.ensureResultUsed(block, fn_ret_ty, call_src);
+            }
+
             const result = result: {
                 sema.analyzeBody(&child_block, fn_info.body) catch |err| switch (err) {
                     error.ComptimeReturn => break :result inlining.comptime_result,
@@ -6763,7 +6766,7 @@ fn analyzeCall(
     };
 
     if (ensure_result_used) {
-        try sema.ensureResultUsed(block, result, call_src);
+        try sema.ensureResultUsed(block, sema.typeOf(result), call_src);
     }
     if (call_tag == .call_always_tail) {
         return sema.handleTailCall(block, call_src, func_ty, result);
@@ -7406,7 +7409,7 @@ fn instantiateGenericCall(
     sema.appendRefsAssumeCapacity(runtime_args);
 
     if (ensure_result_used) {
-        try sema.ensureResultUsed(block, result, call_src);
+        try sema.ensureResultUsed(block, sema.typeOf(result), call_src);
     }
     if (call_tag == .call_always_tail) {
         return sema.handleTailCall(block, call_src, func_ty, result);
diff --git a/test/cases/compile_errors/ignored_comptime_value.zig b/test/cases/compile_errors/ignored_comptime_value.zig
@@ -1,6 +1,18 @@
-export fn foo() void {
+export fn a() void {
     comptime 1;
 }
+export fn b() void {
+    comptime bar();
+}
+fn bar() u8 {
+    const u32_max = @import("std").math.maxInt(u32);
+
+    @setEvalBranchQuota(u32_max);
+    var x: u32 = 0;
+    while (x != u32_max) : (x +%= 1) {}
+
+    return 0;
+}
 
 // error
 // backend=stage2
@@ -9,3 +21,6 @@ export fn foo() void {
 // :2:5: error: value of type 'comptime_int' ignored
 // :2:5: note: all non-void values must be used
 // :2:5: note: this error can be suppressed by assigning the value to '_'
+// :5:17: error: value of type 'u8' ignored
+// :5:17: note: all non-void values must be used
+// :5:17: note: this error can be suppressed by assigning the value to '_'