From: Matthew Maurer <mmaurer@google.com>
To: musl@lists.openwall.com
Subject: [PATCH] Use __attribute__((noreturn)) for function pointer
Date: Fri, 14 Jun 2019 09:42:09 -0700 [thread overview]
Message-ID: <CAGSQo023ouvBT1ivVaYJ7XXyvmnsaN==_61Xg39=djEn_xrZdg@mail.gmail.com> (raw)
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_Noreturn doesn't actually exist in C99 - that's a C11ism. Even in C11, it
cannot be used on a function pointer type.
__attribute__((noreturn)) is a GNU C extension (which we're allowed to use,
unlike C11), and is allowed to be placed on function pointer types.
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From adeca3acc1e4c1b727e8524542c201b436ba8a5b Mon Sep 17 00:00:00 2001
From: Matthew Maurer <mmaurer@google.com>
Date: Thu, 13 Jun 2019 12:33:38 -0700
Subject: [PATCH] Use __attribute__((noreturn)) for function pointer
_Noreturn is a C11 construct, and may only be used at the site of a
function definition.
__attribute__((noreturn)) is a GNU C extension which may be used on
function pointers.
GCC with any standard permits _Noreturn in the position it's used
(likely because it implements it in terms of attribute noreturn), but
Clang will reject it for any standard past C11, and warn pre-C11.
Musl is written in C99 with GNU C extensions, so
__attribute__((noreturn)) is both more correct in that sense and allows
us to compile with Clang set to higher language standards.
---
src/internal/dynlink.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/src/internal/dynlink.h b/src/internal/dynlink.h
index cbe0a6fe..d2bf6b41 100644
--- a/src/internal/dynlink.h
+++ b/src/internal/dynlink.h
@@ -95,7 +95,7 @@ struct fdpic_dummy_loadmap {
#define DYN_CNT 32
typedef void (*stage2_func)(unsigned char *, size_t *);
-typedef _Noreturn void (*stage3_func)(size_t *);
+typedef __attribute__((noreturn)) void (*stage3_func)(size_t *);
hidden void *__dlsym(void *restrict, const char *restrict, void *restrict);
--
2.22.0.410.gd8fdbe21b5-goog
next reply other threads:[~2019-06-14 16:42 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-06-14 16:42 Matthew Maurer [this message]
2019-06-14 16:47 ` Rich Felker
2019-06-14 16:50 ` Matthew Maurer
2019-06-25 22:58 ` Rich Felker
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