Commit 24babde746621492c5111ffcd8edf575cb176d65 | zig

author	Matthew Lugg <mlugg@mlugg.co.uk> 2024-10-31 02:32:34+00:00
committer	Matthew Lugg <mlugg@mlugg.co.uk> 2024-10-31 20:42:53+00:00
log	24babde746621492c5111ffcd8edf575cb176d65
tree	c5f7affd52d47632874da1f533c888ef648e8304
parent	d11bbde5f9c64ef58405604601d55f88bb5d5f3a
signature	Commit is signed but in an unrecognized format.

std.mem.asBytes: fix footgun when passing non-single pointer

I was just bitten by this footgun, where I actually wanted
`sliceAsBytes` but unintentionally used `asBytes`, which in practice
ignored all but the first element. Just add a comptime assertion to
trigger a compile error in this case.

1 files changed, 3 insertions(+), 1 deletions(-)

lib
- std
  - mem.zig

lib/std/mem.zig+3-1

 @@ -3965,7 +3965,9 @@ fn CopyPtrAttrs(
 }
 fn AsBytesReturnType(comptime P: type) type {
-    const size = @sizeOf(std.meta.Child(P));
+    const pointer = @typeInfo(P).pointer;
+    assert(pointer.size == .One);
+    const size = @sizeOf(pointer.child);
     return CopyPtrAttrs(P, .One, [size]u8);
 }