Hi all:

uclibc seem will set argument *memptr to NULL when posix_memalign[1] fail, I know it's not specify in most document[1-3], but other libc (newlib, glibc, musl) implementations are not set it to NULL if fail and gcc testsuite have 1 test case for that[7], so how about make uclib consistent to other libc?

the patch attached.

newlib[4]: int __posix_memalign (void **memptr, size_t alignment, size_t size) { void *mem;

/* Test whether the ALIGNMENT argument is valid. It must be a power of two multiple of sizeof (void *). */ if (alignment % sizeof (void *) != 0 || (alignment & (alignment - 1)) != 0) return EINVAL;

mem = __libc_memalign (alignment, size);

if (mem != NULL) // only set when success { *memptr = mem; return 0; }

return ENOMEM; }

glibc [5]: int __posix_memalign (void **memptr, size_t alignment, size_t size) { void *mem;

/* Test whether the SIZE argument is valid. It must be a power of two multiple of sizeof (void *). */ if (alignment % sizeof (void *) != 0 || !powerof2 (alignment / sizeof (void *)) != 0 || alignment == 0) return EINVAL;

/* Call the hook here, so that caller is posix_memalign's caller and not posix_memalign itself. */ void *(*hook) (size_t, size_t, const void *) = force_reg (__memalign_hook); if (__builtin_expect (hook != NULL, 0)) mem = (*hook)(alignment, size, RETURN_ADDRESS (0)); else mem = __libc_memalign (alignment, size);

if (mem != NULL) { // only set when success *memptr = mem; return 0; }

return ENOMEM; }

musl [6]: int posix_memalign(void **res, size_t align, size_t len) { if (align < sizeof(void *)) return EINVAL; void *mem = __memalign(align, len); if (!mem) return errno; *res = mem; // only set when success return 0; }

[1] http://man7.org/linux/man-pages/man3/posix_memalign.3.html [2] http://pubs.opengroup.org/onlinepubs/009695399/ functions/posix_memalign.html [3] https://linux.die.net/man/3/posix_memalign [4] https://sourceware.org/git/gitweb.cgi?p=newlib-cygwin. git;a=blob;f=newlib/libc/sys/linux/malloc.c;h=25007e8896a1292d6ae821aa35d7b8 973ea99bad;hb=HEAD#l4938 [5] https://sourceware.org/git/?p=glibc.git;a=blob;f=malloc/malloc.c;h= 488579390578e09a1a232ac5161daee086dbbd6b;hb=HEAD#l5086 [6] http://git.musl-libc.org/cgit/musl/tree/src/malloc/posix_memalign.c [7] https://github.com/gcc-mirror/gcc/blob/master/gcc/testsuite/ gcc.dg/torture/pr60092.c