Bug 11532 – Variadics using the C ABI should not accept D-specific types

The ABI for C variadics (e.g. printf and friends) does not understand D data types, in particular slices and fixed-size arrays. We should reject statically any passing of D-specific data through C-style variadics. This has been a very nagging issue during a port of a large C codebase.

They do map to C ABI, just not in the way which you may likely expect. I'd +1 fixed size arrays, as it is not obvious that eg: int[4] is passed as struct { int a,b,c,d; } Though I'd really like to make some sort of exception to the va_list type (in particular, for x86_64 and PPC). That has been one nagging problem I haven't yet got round to...

Yeah, this one is a huge pain for DDMD, people are constantly adding ?: with string literals inside printfs. https://github.com/D-Programming-Language/dmd/pull/2797

And running this just found 3 more...

And a couple of cases left in phobos: https://github.com/D-Programming-Language/phobos/pull/1698

Commits pushed to master at https://github.com/D-Programming-Language/phobos https://github.com/D-Programming-Language/phobos/commit/48063576235217b169efa4343008d08f4a6790a7 Fixup for issue 11532 https://github.com/D-Programming-Language/phobos/commit/b2c6179854eee67387e5d41f317269c4c6b8b58e Merge pull request #1698 from yebblies/issue11532 [trivial] Fixup for issue 11532

Commits pushed to master at https://github.com/D-Programming-Language/dmd https://github.com/D-Programming-Language/dmd/commit/419096e305eff06ef889a8d1a23660d4f3d70eb4 Fix Issue 11532 - Variadics using the C ABI should not accept D-specific types https://github.com/D-Programming-Language/dmd/commit/56544eddd0f4536fd7f1f6d4adb82e3fea9ca8d0 Merge pull request #2797 from yebblies/issue11532 Issue 11532 - Variadics using the C ABI should not accept D-specific types

This was fixed but not closed. Marking as WORKSFORME so it doesn't show up in the changelog.