From c1760eaf3b575ad174fd88b252fd16bd525fa818 Mon Sep 17 00:00:00 2001 From: Martin Sebor Date: Sun, 16 May 2021 15:21:18 -0600 Subject: Enable support for GCC 11 -Wmismatched-dealloc. To help detect common kinds of memory (and other resource) management bugs, GCC 11 adds support for the detection of mismatched calls to allocation and deallocation functions. At each call site to a known deallocation function GCC checks the set of allocation functions the former can be paired with and, if the two don't match, issues a -Wmismatched-dealloc warning (something similar happens in C++ for mismatched calls to new and delete). GCC also uses the same mechanism to detect attempts to deallocate objects not allocated by any allocation function (or pointers past the first byte into allocated objects) by -Wfree-nonheap-object. This support is enabled for built-in functions like malloc and free. To extend it beyond those, GCC extends attribute malloc to designate a deallocation function to which pointers returned from the allocation function may be passed to deallocate the allocated objects. Another, optional argument designates the positional argument to which the pointer must be passed. This change is the first step in enabling this extended support for Glibc. --- include/programs/xmalloc.h | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'include') diff --git a/include/programs/xmalloc.h b/include/programs/xmalloc.h index 76e345f4ee..33871e22ef 100644 --- a/include/programs/xmalloc.h +++ b/include/programs/xmalloc.h @@ -23,11 +23,11 @@ /* Prototypes for a few program-wide used functions. */ extern void *xmalloc (size_t n) - __attribute_malloc__ __attribute_alloc_size__ ((1)); + __attribute_malloc__ __attribute_alloc_size__ ((1)) __attr_dealloc_free; extern void *xcalloc (size_t n, size_t s) - __attribute_malloc__ __attribute_alloc_size__ ((1, 2)); + __attribute_malloc__ __attribute_alloc_size__ ((1, 2)) __attr_dealloc_free; extern void *xrealloc (void *o, size_t n) - __attribute_malloc__ __attribute_alloc_size__ ((2)); -extern char *xstrdup (const char *) __attribute_malloc__; + __attribute_malloc__ __attribute_alloc_size__ ((2)) __attr_dealloc_free; +extern char *xstrdup (const char *) __attribute_malloc__ __attr_dealloc_free; #endif /* xmalloc.h */ -- cgit v1.2.3