configure: regroup and expand C header and program checks

[urcu.git] / configure.ac

diff --git a/configure.ac b/configure.ac
index 30d2056656ed471727311899b9ddba7b50fe517e..10d4ff0041b1b5507733dd131739fb41dfb1898f 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -55,6 +55,83 @@ AS_CASE([$host],
 )
 
 
+##                   ##
+## C compiler checks ##
+##                   ##
+
+# Choose the C compiler
+AC_PROG_CC
+# AC_PROG_CC_STDC was merged in AC_PROG_CC in autoconf 2.70
+m4_version_prereq([2.70], [], [AC_PROG_CC_STDC])
+
+# Make sure the C compiler supports C99
+AS_IF([test "$ac_cv_prog_cc_c99" = "no"], [AC_MSG_ERROR([The compiler does not support C99])])
+
+# Enable available system extensions and LFS support
+AC_USE_SYSTEM_EXTENSIONS
+AC_SYS_LARGEFILE
+
+# Make sure the C compiler supports __attribute__
+AX_C___ATTRIBUTE__
+AS_IF([test "x$ax_cv___attribute__" != "xyes"],
+  [AC_MSG_ERROR([The compiler does not support __attribute__ extensions])])
+
+# Make sure we have pthread support
+AX_PTHREAD([], [AC_MSG_ERROR([Could not configure pthread support])])
+
+# Make sure the C compiler supports weak symbols
+AX_SYS_WEAK_ALIAS
+AS_IF([test "x$ax_cv_sys_weak_alias" = "xno"],
+  [AC_MSG_ERROR([Your platform doesn't support weak symbols.])])
+
+# Checks for typedefs, structures, and compiler characteristics.
+AC_C_INLINE
+AC_C_TYPEOF
+AC_TYPE_INT32_T
+AC_TYPE_PID_T
+AC_TYPE_SIZE_T
+AC_TYPE_SSIZE_T
+AC_TYPE_UINT16_T
+AC_TYPE_UINT32_T
+AC_TYPE_UINT64_T
+AC_TYPE_UINT8_T
+
+
+##               ##
+## Header checks ##
+##               ##
+
+AC_HEADER_STDBOOL
+AC_CHECK_HEADERS([ \
+       limits.h \
+       stddef.h \
+       sys/param.h \
+       sys/time.h \
+])
+
+
+##                 ##
+## Programs checks ##
+##                 ##
+
+AC_PROG_AWK
+AC_PROG_GREP
+AC_PROG_MAKE_SET
+AC_CHECK_PROGS(NPROC, [nproc gnproc])
+AC_CHECK_PROG(GETCONF, [getconf])
+AS_IF([test "x$NPROC" != "x"],
+       [NPROC_CMD=$NPROC],
+       [AS_IF([test "x$GETCONF" != "x"],
+               [NPROC_CMD="$GETCONF _NPROCESSORS_ONLN"],
+               [NPROC_CMD="echo 1"]
+       )]
+)
+AC_SUBST([NPROC_CMD], [$NPROC_CMD])
+
+# Initialize and configure libtool
+LT_INIT
+
+
 AH_TEMPLATE([CONFIG_RCU_SMP], [Enable SMP support. With SMP support enabled, uniprocessors are also supported. With SMP support disabled, UP systems work fine, but the behavior of SMP systems is undefined.])
 AH_TEMPLATE([CONFIG_RCU_TLS], [TLS provided by the compiler.])
 AH_TEMPLATE([CONFIG_RCU_HAVE_CLOCK_GETTIME], [clock_gettime() is detected.])
@@ -76,46 +153,8 @@ AC_ARG_ENABLE([compiler-tls],
        [def_compiler_tls=$enableval],
        [def_compiler_tls="yes"])
 
-# Checks for C compiler
-AC_USE_SYSTEM_EXTENSIONS
-AC_PROG_CC
-# AC_PROG_CC_STDC was merged in AC_PROG_CC in autoconf 2.70
-m4_version_prereq([2.70], [], [AC_PROG_CC_STDC])
 AS_IF([test "x$def_compiler_tls" = "xyes"], AC_DEFINE([CONFIG_RCU_TLS], [1]), [:])
 
-# Checks for programs.
-AC_PROG_AWK
-AC_PROG_MAKE_SET
-AC_CHECK_PROGS(NPROC, [nproc gnproc])
-AC_CHECK_PROGS(GETCONF, [getconf])
-AS_IF([test "x$NPROC" != "x"],
-       [NPROC_CMD=$NPROC],
-       [AS_IF([test "x$GETCONF" != "x"],
-               [NPROC_CMD="$GETCONF _NPROCESSORS_ONLN"],
-               [NPROC_CMD="echo 1"]
-       )]
-)
-AC_SUBST([NPROC_CMD], [$NPROC_CMD])
-
-LT_INIT
-
-# Checks for typedefs, structures, and compiler characteristics.
-AC_C_INLINE
-AC_TYPE_PID_T
-AC_TYPE_SIZE_T
-AC_TYPE_SSIZE_T
-AC_TYPE_UINT16_T
-AC_TYPE_INT32_T
-AC_TYPE_UINT32_T
-AC_TYPE_UINT64_T
-AC_TYPE_UINT8_T
-
-AX_C___ATTRIBUTE__
-AS_IF([test "x$ax_cv___attribute__" = "xyes"],
-       [:],
-       [AC_MSG_ERROR([The compiler does not support __attribute__ extensions])])
-
-AX_PTHREAD(,[AC_MSG_ERROR([Could not configure pthreads support])])
 
 AM_CFLAGS="$AM_CFLAGS $PTHREAD_CFLAGS"
 
@@ -140,15 +179,6 @@ AC_CHECK_FUNCS([ \
 # AC_FUNC_MALLOC causes problems when cross-compiling.
 #AC_FUNC_MALLOC
 
-# Check for headers
-AC_HEADER_STDBOOL
-AC_CHECK_HEADERS([ \
-       limits.h \
-       stddef.h \
-       sys/param.h \
-       sys/time.h \
-])
-
 # Search for clock_gettime
 AC_SEARCH_LIBS([clock_gettime], [rt], [
        AC_DEFINE([CONFIG_RCU_HAVE_CLOCK_GETTIME], [1])