[lbtt] Adjust to support the Intel compiler (icpc).

* configure.ac: Adjust to call...
    * m4/intel.m4: ...this new macro.
    * Makefile.am: Add the directory `m4' as an includedir of
    autoconf's macros.

lbtt/ChangeLog

@@ -1,3 +1,12 @@
+2009-06-12  Guillaume Sadegh  <sadegh@lrde.epita.fr>
+
+	Adjust to support the Intel compiler (icpc).
+
+	* configure.ac: Adjust to call...
+	* m4/intel.m4: ...this new macro.
+	* Makefile.am: Add the directory `m4' as an includedir of
+	autoconf's macros.
+
 2009-05-31  Alexandre Duret-Lutz  <adl@gnu.org>
 
 	Adjust parser to Bison 2.4.1.

lbtt/Makefile.am

@@ -1 +1,2 @@
 SUBDIRS = doc src
+ACLOCAL_AMFLAGS = -I m4

lbtt/configure.ac

@@ -17,7 +17,7 @@ AC_PROG_CXX
 AC_PROG_CXXCPP
 AM_PROG_LEX
 AC_PROG_YACC
-
+lbtt_INTEL
 
 
 # Check whether the user has explicitly disabled support for the GNU readline

lbtt/m4/intel.m4

@@ -0,0 +1,50 @@
+
+dnl Adapted from the predefined _AC_LANG_COMPILER_GNU.
+m4_define([_AC_LANG_COMPILER_INTEL],
+[AC_CACHE_CHECK([whether we are using the INTEL _AC_LANG compiler],
+		[ac_cv_[]_AC_LANG_ABBREV[]_compiler_intel],
+[
+_AC_COMPILE_IFELSE([AC_LANG_PROGRAM([], [[#ifndef __INTEL_COMPILER
+       choke me
+#endif
+]])],
+		   [ac_compiler_intel=yes],
+		   [ac_compiler_intel=no])
+ac_cv_[]_AC_LANG_ABBREV[]_compiler_intel=$ac_compiler_intel
+])])# _AC_LANG_COMPILER_INTEL
+
+dnl The list of warnings that must be disabled.
+m4_define([_INTEL_IGNORE_WARNINGS],
+[ 913  dnl Warn when multibyte character are used (for example "Büchi").
+]) # _INTEL_IGNORE_WARNINGS
+
+dnl Add extra flags when icpc is used.
+AC_DEFUN([lbtt_INTEL],
+[_AC_LANG_COMPILER_INTEL
+AC_CACHE_CHECK([to add extra CXXFLAGS for the INTEL C++ compiler],
+		[ac_cv_intel_cxxflags],
+[ dnl
+  if test x"$ac_compiler_intel" = x"yes"; then
+    # -W does not exist for icpc in CXXFLAGS.
+    CXXFLAGS=`echo "$CXXFLAGS" | sed 's/-W[[[:space:]]]//g;s/-W$//'`
+
+    disabled_warnings=''
+    for warning in _INTEL_IGNORE_WARNINGS; do
+      disabled_warnings="$disabled_warnings,$warning"
+    done
+
+    # Remove the extra "," and extra whitespaces.
+    disabled_warnings=`echo "$disabled_warnings" | sed "s/^,//;s/[[[:space:]]]//g"`
+
+    INTEL_CXXFLAGS="-w1 -Werror -wd${disabled_warnings}"
+
+    # Even if the icpc preprocessor defines __GNUC__, it is not a GNU compiler.
+    GXX=
+    CXXFLAGS="$CXXFLAGS $INTEL_CXXFLAGS"
+
+    [ac_cv_intel_cxxflags="$INTEL_CXXFLAGS"]
+  else
+    [ac_cv_intel_cxxflags="no extra flags"]
+  fi])
+  AC_SUBST([INTEL_CXXFLAGS])
+]) # lbtt_INTEL