From 98b0c66968ab6bf4ec85b36c58a4026bbd28d4fd Mon Sep 17 00:00:00 2001 From: Jim Meyering Date: Wed, 12 Feb 2003 17:47:51 +0000 Subject: (ACX_C_RESTRICT): Remove #ifndef -- so now this macro also checks for support when using a C++ compiler. Also, remove the test for SGI's __restrict. Suggested by Steven G. Johnson. --- m4/restrict.m4 | 27 +++++++++++---------------- 1 file changed, 11 insertions(+), 16 deletions(-) (limited to 'm4') diff --git a/m4/restrict.m4 b/m4/restrict.m4 index 902dc1308..ca4f70f0b 100644 --- a/m4/restrict.m4 +++ b/m4/restrict.m4 @@ -1,26 +1,21 @@ -#serial 1000 +#serial 1001 dnl based on acx_restrict.m4, from the GNU Autoconf Macro Archive at: dnl http://www.gnu.org/software/ac-archive/htmldoc/acx_restrict.html -# Determine whether the C compiler supports the "restrict" keyword introduced -# in ANSI C99, or an equivalent. Do nothing if the compiler accepts it. -# Otherwise, if the compiler supports an equivalent (like gcc's __restrict__) -# define "restrict" to be that. Otherwise, define "restrict" to be empty. +# Determine whether the C/C++ compiler supports the "restrict" keyword +# introduced in ANSI C99, or an equivalent. Do nothing if the compiler +# accepts it. Otherwise, if the compiler supports an equivalent (like +# gcc's __restrict__) define "restrict" to be that. Otherwise, define +# "restrict" to be empty. AC_DEFUN([ACX_C_RESTRICT], -[AC_CACHE_CHECK([for C restrict keyword], acx_cv_c_restrict, +[AC_CACHE_CHECK([for C/C++ restrict keyword], acx_cv_c_restrict, [acx_cv_c_restrict=no - # Try the official restrict keyword, then gcc's __restrict__, then - # SGI's __restrict. __restrict has slightly different semantics than - # restrict (it's a bit stronger, in that __restrict pointers can't - # overlap even with non __restrict pointers), but I think it should be - # okay under the circumstances where restrict is normally used. - for acx_kw in restrict __restrict__ __restrict; do + # Try the official restrict keyword, then gcc's __restrict__. + for acx_kw in restrict __restrict__; do AC_COMPILE_IFELSE([AC_LANG_SOURCE( - [#ifndef __cplusplus - float * $acx_kw x; -#endif - ])], [acx_cv_c_restrict=$acx_kw; break]) + [float * $acx_kw x;])], + [acx_cv_c_restrict=$acx_kw; break]) done ]) case $acx_cv_c_restrict in -- cgit v1.2.3-70-g09d2