configure: autotools compatibility fixes - step I

Fix proper macro expansion order across autotools versions for
C compiler and preprocessor program checks.

1 files changed, 102 insertions, 0 deletions

diff --git a/m4/xc-cc-check.m4 b/m4/xc-cc-check.m4
new file mode 100644
index 000000000..5e5af9c69
--- /dev/null
+++ b/m4/xc-cc-check.m4
@@ -0,0 +1,102 @@
+#---------------------------------------------------------------------------
+#
+# xc-cc-check.m4
+#
+# Copyright (c) 2013 Daniel Stenberg <daniel@haxx.se>
+#
+# Permission to use, copy, modify, and distribute this software for any
+# purpose with or without fee is hereby granted, provided that the above
+# copyright notice and this permission notice appear in all copies.
+#
+# THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+# WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+# MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+# ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+# WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+# ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+# OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+#
+#---------------------------------------------------------------------------
+
+# serial 1
+
+
+dnl _XC_PROG_CC_PREAMBLE
+dnl -------------------------------------------------
+dnl Private macro.
+
+AC_DEFUN([_XC_PROG_CC_PREAMBLE], [
+  xc_prog_cc_prev_IFS=$IFS
+  xc_prog_cc_prev_LIBS=$LIBS
+  xc_prog_cc_prev_CFLAGS=$CFLAGS
+  xc_prog_cc_prev_LDFLAGS=$LDFLAGS
+  xc_prog_cc_prev_CPPFLAGS=$CPPFLAGS
+])
+
+
+dnl _XC_PROG_CC_POSTLUDE
+dnl -------------------------------------------------
+dnl Private macro.
+
+AC_DEFUN([_XC_PROG_CC_POSTLUDE], [
+  IFS=$xc_prog_cc_prev_IFS
+  LIBS=$xc_prog_cc_prev_LIBS
+  CFLAGS=$xc_prog_cc_prev_CFLAGS
+  LDFLAGS=$xc_prog_cc_prev_LDFLAGS
+  CPPFLAGS=$xc_prog_cc_prev_CPPFLAGS
+  export CC
+  export CPP
+  export LIBS
+  export CFLAGS
+  export LDFLAGS
+  export CPPFLAGS
+  AC_SUBST([CC])dnl
+  AC_SUBST([CPP])dnl
+  AC_SUBST([LIBS])dnl
+  AC_SUBST([CFLAGS])dnl
+  AC_SUBST([LDFLAGS])dnl
+  AC_SUBST([CPPFLAGS])dnl
+])
+
+
+dnl _XC_PROG_CC
+dnl -------------------------------------------------
+dnl Private macro.
+
+AC_DEFUN([_XC_PROG_CC], [
+  AC_REQUIRE([_XC_PROG_CC_PREAMBLE])dnl
+  AC_REQUIRE([XC_CHECK_USER_FLAGS])dnl
+  AC_REQUIRE([AC_PROG_INSTALL])dnl
+  AC_REQUIRE([AC_PROG_CC])dnl
+  AC_REQUIRE([AM_PROG_CC_C_O])dnl
+  AC_REQUIRE([AC_PROG_CPP])dnl
+  AC_REQUIRE([_XC_PROG_CC_POSTLUDE])dnl
+])
+
+
+dnl XC_CHECK_PROG_CC
+dnl -------------------------------------------------
+dnl Public macro.
+dnl
+dnl Checks for C compiler and C preprocessor programs,
+dnl while doing some previous sanity validation on user
+dnl provided LIBS, LDFLAGS, CPPFLAGS and CFLAGS values
+dnl that must succeed in order to continue execution.
+dnl
+dnl This sets variables CC and CPP, while preventing
+dnl LIBS, LDFLAGS, CFLAGS, CPPFLAGS and IFS from being
+dnl unexpectedly changed by underlying macros.
+
+AC_DEFUN([XC_CHECK_PROG_CC], [
+  AC_PREREQ([2.50])dnl
+  AC_BEFORE([$0],[_XC_PROG_CC_PREAMBLE])dnl
+  AC_BEFORE([$0],[AC_PROG_INSTALL])dnl
+  AC_BEFORE([$0],[AC_PROG_CC])dnl
+  AC_BEFORE([$0],[AM_PROG_CC_C_O])dnl
+  AC_BEFORE([$0],[AC_PROG_CPP])dnl
+  AC_BEFORE([$0],[AC_PROG_LIBTOOL])dnl
+  AC_BEFORE([$0],[AM_INIT_AUTOMAKE])dnl
+  AC_BEFORE([$0],[_XC_PROG_CC_POSTLUDE])dnl
+  AC_REQUIRE([_XC_PROG_CC])dnl
+])
+