diff options
Diffstat (limited to 'lgl/m4/gnulib-common.m4')
| -rw-r--r-- | lgl/m4/gnulib-common.m4 | 45 |
1 files changed, 44 insertions, 1 deletions
diff --git a/lgl/m4/gnulib-common.m4 b/lgl/m4/gnulib-common.m4 index 539801080d..9336d72605 100644 --- a/lgl/m4/gnulib-common.m4 +++ b/lgl/m4/gnulib-common.m4 @@ -1,4 +1,4 @@ -# gnulib-common.m4 serial 2 +# gnulib-common.m4 serial 3 dnl Copyright (C) 2007 Free Software Foundation, Inc. dnl This file is free software; the Free Software Foundation dnl gives unlimited permission to copy and/or distribute it, @@ -20,3 +20,46 @@ m4_ifdef([AC_PROG_MKDIR_P], [], [ [AC_REQUIRE([AM_PROG_MKDIR_P])dnl defined by automake MKDIR_P='$(mkdir_p)' AC_SUBST([MKDIR_P])])]) + +# AC_C_RESTRICT +# This definition overrides the AC_C_RESTRICT macro from autoconf 2.60..2.61, +# so that mixed use of GNU C and GNU C++ and mixed use of Sun C and Sun C++ +# works. +# This definition can be removed once autoconf >= 2.62 can be assumed. +AC_DEFUN([AC_C_RESTRICT], +[AC_CACHE_CHECK([for C/C++ restrict keyword], ac_cv_c_restrict, + [ac_cv_c_restrict=no + # The order here caters to the fact that C++ does not require restrict. + for ac_kw in __restrict __restrict__ _Restrict restrict; do + AC_COMPILE_IFELSE([AC_LANG_PROGRAM( + [[typedef int * int_ptr; + int foo (int_ptr $ac_kw ip) { + return ip[0]; + }]], + [[int s[1]; + int * $ac_kw t = s; + t[0] = 0; + return foo(t)]])], + [ac_cv_c_restrict=$ac_kw]) + test "$ac_cv_c_restrict" != no && break + done + ]) + AH_VERBATIM([restrict], +[/* Define to the equivalent of the C99 'restrict' keyword, or to + nothing if this is not supported. Do not define if restrict is + supported directly. */ +#undef restrict +/* Work around a bug in Sun C++: it does not support _Restrict, even + though the corresponding Sun C compiler does, which causes + "#define restrict _Restrict" in the previous line. Perhaps some future + version of Sun C++ will work with _Restrict; if so, it'll probably + define __RESTRICT, just as Sun C does. */ +#if defined __SUNPRO_CC && !defined __RESTRICT +# define _Restrict +#endif]) + case $ac_cv_c_restrict in + restrict) ;; + no) AC_DEFINE([restrict], []) ;; + *) AC_DEFINE_UNQUOTED([restrict], [$ac_cv_c_restrict]) ;; + esac +]) |