Commit e382e7be2b7a4c40a8db78dca0de38141dad8c67 | zig

Fixes #10797

2 files changed, 14 insertions(+), 3 deletions(-)

lib/std/mem.zig+4-3

...	...	@@ -309,9 +309,7 @@ pub fn zeroes(comptime T: type) T {
309	309	if (comptime meta.containerLayout(T) == .Extern) {
310	310	// The C language specification states that (global) unions
311	311	// should be zero initialized to the first named member.
312		var item: T = undefined;
313		@field(item, info.fields[0].name) = zeroes(@TypeOf(@field(item, info.fields[0].name)));
314		return item;
	312	return @unionInit(T, info.fields[0].name, zeroes(info.fields[0].field_type));
315	313	}
316	314
317	315	@compileError("Can't set a " ++ @typeName(T) ++ " to zero.");
...	...	@@ -417,6 +415,9 @@ test "mem.zeroes" {
417	415
418	416	var c = zeroes(C_union);
419	417	try testing.expectEqual(@as(u8, 0), c.a);
	418
	419	comptime var comptime_union = zeroes(C_union);
	420	try testing.expectEqual(@as(u8, 0), comptime_union.a);
420	421	}
421	422
422	423	/// Initializes all fields of the struct with their default value, or zero values if no default value is present.

test/run_translated_c.zig+10

...	...	@@ -1819,4 +1819,14 @@ pub fn addCases(cases: *tests.RunTranslatedCContext) void {
1819	1819	\\ return 0;
1820	1820	\\}
1821	1821	, "");
	1822
	1823	cases.add("Zero-initialization of global union. Issue #10797",
	1824	\\#include <stdlib.h>
	1825	\\union U { int x; double y; };
	1826	\\union U u;
	1827	\\int main(void) {
	1828	\\ if (u.x != 0) abort();
	1829	\\ return 0;
	1830	\\}
	1831	, "");
1822	1832	}