From a1561c3bbe8e72c6e44280d1eb5e529d2da4ecd0 Mon Sep 17 00:00:00 2001 From: Martin Sebor Date: Tue, 27 Apr 2021 13:01:55 -0600 Subject: Add __attribute_access_none to disable GCC warnings [BZ #27714] GCC 11 warns when a pointer to an uninitialized object is passed to a function that takes a const-qualified argument. This is done on the assumption that most such functions read from the object. For the rare case of a function that doesn't, GCC 11 extends attribute access to add a new mode called none. POSIX pthread_setspecific() is one such rare function that takes a const void* argument but that doesn't read from the object it points to. To suppress the -Wmaybe-uninitialized issued by GCC 11 when the address of an uninitialized object is passed to it (e.g., the result of malloc()), this change #defines __attr_access_none in cdefs.h and uses the macro on the function in sysdeps/htl/pthread.h and sysdeps/nptl/pthread.h. --- misc/sys/cdefs.h | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) (limited to 'misc/sys') diff --git a/misc/sys/cdefs.h b/misc/sys/cdefs.h index 8e244a77cf..11f01f741b 100644 --- a/misc/sys/cdefs.h +++ b/misc/sys/cdefs.h @@ -592,9 +592,15 @@ _Static_assert (0, "IEEE 128-bits long double requires redirection on this platf array according to access mode, or at least one element when size-index is not provided: access (access-mode, [, ]) */ -#define __attr_access(x) __attribute__ ((__access__ x)) +# define __attr_access(x) __attribute__ ((__access__ x)) +# if __GNUC_PREREQ (11, 0) +# define __attr_access_none(argno) __attribute__ ((__access__ (__none__, argno))) +# else +# define __attr_access_none(argno) +# endif #else # define __attr_access(x) +# define __attr_access_none(argno) #endif /* Specify that a function such as setjmp or vfork may return -- cgit v1.2.3