Fix aliasing-based undefined behavior in string functions. #11215
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zekoz
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Can you mention this in |
Copies these functions verbatim from musl v1.2.0. Also adds weak_alias macro to features.h to reflect upstream musl.
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| @@ -33,4 +33,7 @@ | |||
| #define _Noreturn | |||
| #endif | |||
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| #define weak_alias(old, new) \ | |||
| extern __typeof(old) new __attribute__((__weak__, __alias__(#old))) | |||
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This looks like its already defined in src/internal/libc.h.. And in upstream musl it moved to the internal header src/include/features.h (as opposed to this features.h header which is externally visible).
Is this a necessary part of the change? Do the sources in string not already include src/internal/libc.h?
I wonder if its worth bringing over the new src/include/features.h wrapper header?
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Well, you nerd-sniped me. I am seeing how much v1.2.0 I can pull in here.
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If possible I'd recommend keeping this change focused, unless you want to do a full musl upgrade .. which is quite a big endeavor. (I think it took weeks or maybe months to completely last time it was done).
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I agree, let's land this now, but @zekoz please submit more PRs with more 1.2 pieces or even the whole upgrade!
This was added in #11215 to maintain comatability with upgraded version of stpcpy.c/stpncpy.c/strchrnul.c. However, this macro was never indended to exposed outside of musl itself. In musl v1.2.2 this macro lives in the *internal* version of features.h but musl v1.1.15 does't have an internal features.h. Instead this macro lives in libc.h in v1.1.15. See: #14352 Fixes: #14350
This was added in #11215 to maintain comatability with upgraded version of stpcpy.c/stpncpy.c/strchrnul.c. However, this macro was never indended to exposed outside of musl itself. In musl v1.2.2 this macro lives in the *internal* version of features.h but musl v1.1.15 does't have an internal features.h. Instead this macro lives in libc.h in v1.1.15. See: #14352 Fixes: #14350
Copies these functions verbatim from musl v1.2.0. #10910 #7279