add C ABI tests for exotic float types

test/c_abi/cfuncs.c

@@ -4,7 +4,7 @@
 #include <stdlib.h>
 #include <string.h>
 
-void zig_panic();
+void zig_panic(void);
 
 static void assert_or_panic(bool ok) {
     if (!ok) {
@@ -60,6 +60,54 @@ static void assert_or_panic(bool ok) {
 #  define ZIG_NO_COMPLEX
 #endif
 
+#ifdef __x86_64__
+#define ZIG_NO_RAW_F16
+#endif
+
+#ifdef __i386__
+#define ZIG_NO_RAW_F16
+#endif
+
+#ifdef __mips__
+#define ZIG_NO_RAW_F16
+#endif
+
+#ifdef __riscv
+#define ZIG_NO_RAW_F16
+#endif
+
+#ifdef __wasm__
+#define ZIG_NO_RAW_F16
+#endif
+
+#ifdef __powerpc__
+#define ZIG_NO_RAW_F16
+#endif
+
+#ifdef __aarch64__
+#define ZIG_NO_F128
+#endif
+
+#ifdef __arm__
+#define ZIG_NO_F128
+#endif
+
+#ifdef __mips__
+#define ZIG_NO_F128
+#endif
+
+#ifdef __riscv
+#define ZIG_NO_F128
+#endif
+
+#ifdef __powerpc__
+#define ZIG_NO_F128
+#endif
+
+#ifdef __APPLE__
+#define ZIG_NO_F128
+#endif
+
 #ifndef ZIG_NO_I128
 struct i128 {
     __int128 value;
@@ -884,3 +932,56 @@ void c_func_ptr_byval(void *a, void *b, struct ByVal in, unsigned long c, void *
     assert_or_panic((intptr_t)d == 4);
     assert_or_panic(e == 5);
 }
+
+#ifndef ZIG_NO_RAW_F16
+__fp16 c_f16(__fp16 a) {
+    assert_or_panic(a == 12);
+    return 34;
+}
+#endif
+
+typedef struct {
+    __fp16 a;
+} f16_struct;
+f16_struct c_f16_struct(f16_struct a) {
+    assert_or_panic(a.a == 12);
+    return (f16_struct){34};
+}
+
+#if defined __x86_64__ || defined __i386__
+typedef long double f80;
+f80 c_f80(f80 a) {
+    assert_or_panic((double)a == 12.34);
+    return 56.78;
+}
+typedef struct {
+    f80 a;
+} f80_struct;
+f80_struct c_f80_struct(f80_struct a) {
+    assert_or_panic((double)a.a == 12.34);
+    return (f80_struct){56.78};
+}
+typedef struct {
+    f80 a;
+    int b;
+} f80_extra_struct;
+f80_extra_struct c_f80_extra_struct(f80_extra_struct a) {
+    assert_or_panic((double)a.a == 12.34);
+    assert_or_panic(a.b == 42);
+    return (f80_extra_struct){56.78, 24};
+}
+#endif
+
+#ifndef ZIG_NO_F128
+__float128 c_f128(__float128 a) {
+    assert_or_panic((double)a == 12.34);
+    return 56.78;
+}
+typedef struct {
+    __float128 a;
+} f128_struct;
+f128_struct c_f128_struct(f128_struct a) {
+    assert_or_panic((double)a.a == 12.34);
+    return (f128_struct){56.78};
+}
+#endif

test/c_abi/main.zig

@@ -13,6 +13,9 @@ const expectEqual = std.testing.expectEqual;
 const has_i128 = builtin.cpu.arch != .x86 and !builtin.cpu.arch.isARM() and
     !builtin.cpu.arch.isMIPS() and !builtin.cpu.arch.isPPC();
 
+const has_f128 = builtin.cpu.arch.isX86() and !builtin.os.tag.isDarwin();
+const has_f80 = builtin.cpu.arch.isX86();
+
 extern fn run_c_tests() void;
 
 export fn zig_panic() noreturn {
@@ -1069,3 +1072,80 @@ test "C function that takes byval struct called via function pointer" {
         @as(c_ulong, 5),
     );
 }
+
+extern fn c_f16(f16) f16;
+test "f16 bare" {
+    if (!comptime builtin.cpu.arch.isAARCH64()) return error.SkipZigTest;
+
+    const a = c_f16(12);
+    try expect(a == 34);
+}
+
+const f16_struct = extern struct {
+    a: f16,
+};
+extern fn c_f16_struct(f16_struct) f16_struct;
+test "f16 struct" {
+    if (builtin.target.cpu.arch == .x86) return error.SkipZigTest;
+    if (comptime builtin.target.cpu.arch.isMIPS()) return error.SkipZigTest;
+    if (comptime builtin.target.cpu.arch.isPPC()) return error.SkipZigTest;
+    if (comptime builtin.target.cpu.arch.isPPC()) return error.SkipZigTest;
+    if (comptime builtin.cpu.arch.isARM() and builtin.mode != .Debug) return error.SkipZigTest;
+
+    const a = c_f16_struct(.{ .a = 12 });
+    try expect(a.a == 34);
+}
+
+extern fn c_f80(f80) f80;
+test "f80 bare" {
+    if (!has_f80) return error.SkipZigTest;
+
+    const a = c_f80(12.34);
+    try expect(@floatCast(f64, a) == 56.78);
+}
+
+const f80_struct = extern struct {
+    a: f80,
+};
+extern fn c_f80_struct(f80_struct) f80_struct;
+test "f80 struct" {
+    if (!has_f80) return error.SkipZigTest;
+    if (builtin.target.cpu.arch == .x86) return error.SkipZigTest;
+    if (builtin.mode != .Debug) return error.SkipZigTest;
+
+    const a = c_f80_struct(.{ .a = 12.34 });
+    try expect(@floatCast(f64, a.a) == 56.78);
+}
+
+const f80_extra_struct = extern struct {
+    a: f80,
+    b: c_int,
+};
+extern fn c_f80_extra_struct(f80_extra_struct) f80_extra_struct;
+test "f80 extra struct" {
+    if (!has_f80) return error.SkipZigTest;
+    if (builtin.target.cpu.arch == .x86) return error.SkipZigTest;
+
+    const a = c_f80_extra_struct(.{ .a = 12.34, .b = 42 });
+    try expect(@floatCast(f64, a.a) == 56.78);
+    try expect(a.b == 24);
+}
+
+extern fn c_f128(f128) f128;
+test "f128 bare" {
+    if (!has_f128) return error.SkipZigTest;
+
+    const a = c_f128(12.34);
+    try expect(@floatCast(f64, a) == 56.78);
+}
+
+const f128_struct = extern struct {
+    a: f128,
+};
+extern fn c_f128_struct(f128_struct) f128_struct;
+test "f128 struct" {
+    if (!has_f128) return error.SkipZigTest;
+
+    const a = c_f128_struct(.{ .a = 12.34 });
+    try expect(@floatCast(f64, a.a) == 56.78);
+}