Mercurial > gnulib
changeset 18387:6821cce38136
intprops.h, xalloc-oversized.h: work with gcc 7
In gcc 6, __builtin_add_overflow, __builtin_sub_overflow and
__builtin_mul_overflow each accept a NULL pointer as the third
argument. However in gcc 7, that is no longer accepted.
Instead, one must use the "_p"-suffixed names, with which, the
third parameter is no longer a pointer.
* lib/intprops.h (_GL_HAS_BUILTIN_OVERFLOW_WITH_NULL): Correct
the definition: not true for gcc 7 and subsequent.
(_GL_HAS_BUILTIN_OVERFLOW_P): Define.
(_GL_ADD_OVERFLOW, _GL_SUBTRACT_OVERFLOW, _GL_MULTIPLY_OVERFLOW):
Provide new definitions for gcc 7 and subsequent.
* lib/xalloc-oversized.h (xalloc_oversized): Provide a definition
that works with gcc-7.
author | Jim Meyering <meyering@fb.com> |
---|---|
date | Mon, 29 Aug 2016 09:45:18 -0700 |
parents | de2e6354b968 |
children | 24d7281d8acb |
files | ChangeLog lib/intprops.h lib/xalloc-oversized.h |
diffstat | 3 files changed, 31 insertions(+), 4 deletions(-) [+] |
line wrap: on
line diff
--- a/ChangeLog Mon Aug 29 09:27:50 2016 -0700 +++ b/ChangeLog Mon Aug 29 09:45:18 2016 -0700 @@ -1,5 +1,19 @@ 2016-08-29 Jim Meyering <meyering@fb.com> + intprops.h, xalloc-oversized.h: work with gcc 7 + In gcc 6, __builtin_add_overflow, __builtin_sub_overflow and + __builtin_mul_overflow each accept a NULL pointer as the third + argument. However in gcc 7, that is no longer accepted. + Instead, one must use the "_p"-suffixed names, with which, the + third parameter is no longer a pointer. + * lib/intprops.h (_GL_HAS_BUILTIN_OVERFLOW_WITH_NULL): Correct + the definition: not true for gcc 7 and subsequent. + (_GL_HAS_BUILTIN_OVERFLOW_P): Define. + (_GL_ADD_OVERFLOW, _GL_SUBTRACT_OVERFLOW, _GL_MULTIPLY_OVERFLOW): + Provide new definitions for gcc 7 and subsequent. + * lib/xalloc-oversized.h (xalloc_oversized): Provide a definition + that works with gcc-7. + intprops.h: fix missing-backslash problems * lib/intprops.h (_GL_ADD_OVERFLOW): Add backslash. (_GL_SUBTRACT_OVERFLOW,_GL_MULTIPLY_OVERFLOW): Likewise.
--- a/lib/intprops.h Mon Aug 29 09:27:50 2016 -0700 +++ b/lib/intprops.h Mon Aug 29 09:45:18 2016 -0700 @@ -229,13 +229,23 @@ : (max) >> (b) < (a)) /* True if __builtin_add_overflow (A, B, P) works when P is null. */ -#define _GL_HAS_BUILTIN_OVERFLOW_WITH_NULL (7 <= __GNUC__) +#define _GL_HAS_BUILTIN_OVERFLOW_WITH_NULL (6 == __GNUC__) + +/* True if __builtin_add_overflow_p (A, B, C) works. */ +#define _GL_HAS_BUILTIN_OVERFLOW_P (7 <= __GNUC__) /* The _GL*_OVERFLOW macros have the same restrictions as the *_RANGE_OVERFLOW macros, except that they do not assume that operands (e.g., A and B) have the same type as MIN and MAX. Instead, they assume that the result (e.g., A + B) has that type. */ -#if _GL_HAS_BUILTIN_OVERFLOW_WITH_NULL +#if _GL_HAS_BUILTIN_OVERFLOW_P +# define _GL_ADD_OVERFLOW(a, b, min, max) \ + __builtin_add_overflow_p (a, b, (a) + (b)) +# define _GL_SUBTRACT_OVERFLOW(a, b, min, max) \ + __builtin_sub_overflow_p (a, b, (a) - (b)) +# define _GL_MULTIPLY_OVERFLOW(a, b, min, max) \ + __builtin_mul_overflow_p (a, b, (a) * (b)) +#elif _GL_HAS_BUILTIN_OVERFLOW_WITH_NULL # define _GL_ADD_OVERFLOW(a, b, min, max) \ __builtin_add_overflow (a, b, (__typeof__ ((a) + (b)) *) 0) # define _GL_SUBTRACT_OVERFLOW(a, b, min, max) \
--- a/lib/xalloc-oversized.h Mon Aug 29 09:27:50 2016 -0700 +++ b/lib/xalloc-oversized.h Mon Aug 29 09:45:18 2016 -0700 @@ -43,9 +43,12 @@ nonnegative. This is a macro, not a function, so that it works correctly even when SIZE_MAX < N. */ -/* GCC 7 __builtin_mul_overflow should easily compute this. See: +#if 7 <= __GNUC__ +# define xalloc_oversized(n, s) __builtin_mul_overflow_p (n, s, (size_t) 1) + +/* GCC 6 __builtin_mul_overflow should easily compute this. See: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68120 */ -#if 7 <= __GNUC__ +#elif 6 == __GNUC__ # define xalloc_oversized(n, s) __builtin_mul_overflow (n, s, (size_t *) NULL) /* GCC 5 and Clang __builtin_mul_overflow needs a temporary, and