configure.ac: Detect GCC's -fdiagnostics-show-caret. Detect GCC's

-ftrack-macro-expansion when configured with --enable-debugging.

Author: wilx

configure

@@ -5255,7 +5255,71 @@ $as_echo "$ac_cv_path_GREP" >&6; }
 
 case $ax_cv_cxx_compiler_vendor in #(
   gnu|clang) :
-    if test "x$enable_warnings" = "xyes"; then :
+    { $as_echo "$as_me:${as_lineno-$LINENO}: checking CXXFLAGS for gcc -fdiagnostics-show-caret" >&5
+$as_echo_n "checking CXXFLAGS for gcc -fdiagnostics-show-caret... " >&6; }
+if ${ax_cv_cxxflags_gcc_option__fdiagnostics_show_caret+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+  ax_cv_cxxflags_gcc_option__fdiagnostics_show_caret="no, unknown"
+
+ ac_ext=cpp
+ac_cpp='$CXXCPP $CPPFLAGS'
+ac_compile='$CXX -c $CXXFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CXX -o conftest$ac_exeext $CXXFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_cxx_compiler_gnu
+
+ ac_save_CXXFLAGS="$CXXFLAGS"
+for ac_arg in "-pedantic -Werror % -fdiagnostics-show-caret"     "-pedantic % -fdiagnostics-show-caret %% no, obsolete"     #
+do CXXFLAGS="$ac_save_CXXFLAGS "`echo $ac_arg | sed -e 's,%%.*,,' -e 's,%,,'`
+   cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+int
+main ()
+{
+return 0;
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_cxx_try_compile "$LINENO"; then :
+  ax_cv_cxxflags_gcc_option__fdiagnostics_show_caret=`echo $ac_arg | sed -e 's,.*% *,,'`; break
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+done
+ CXXFLAGS="$ac_save_CXXFLAGS"
+ ac_ext=cpp
+ac_cpp='$CXXCPP $CPPFLAGS'
+ac_compile='$CXX -c $CXXFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CXX -o conftest$ac_exeext $CXXFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_cxx_compiler_gnu
+
+
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ax_cv_cxxflags_gcc_option__fdiagnostics_show_caret" >&5
+$as_echo "$ax_cv_cxxflags_gcc_option__fdiagnostics_show_caret" >&6; }
+var=$ax_cv_cxxflags_gcc_option__fdiagnostics_show_caret
+case ".$var" in
+     .ok|.ok,*)  ;;
+   .|.no|.no,*)  ;;
+   *)
+   if echo " $CXXFLAGS " | grep " $var " 2>&1 >/dev/null
+   then { { $as_echo "$as_me:${as_lineno-$LINENO}: : CXXFLAGS does contain \$var"; } >&5
+  (: CXXFLAGS does contain $var) 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }
+   else { { $as_echo "$as_me:${as_lineno-$LINENO}: : CXXFLAGS=\"\$CXXFLAGS \$var\""; } >&5
+  (: CXXFLAGS="$CXXFLAGS $var") 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }
+                      CXXFLAGS="$CXXFLAGS $var"
+   fi
+ ;;
+esac
+
+   if test "x$enable_warnings" = "xyes"; then :
   { $as_echo "$as_me:${as_lineno-$LINENO}: checking CXXFLAGS for gcc -Wextra" >&5
 $as_echo_n "checking CXXFLAGS for gcc -Wextra... " >&6; }
 if ${ax_cv_cxxflags_gcc_option__Wextra+:} false; then :
@@ -6465,6 +6529,70 @@ fi
 { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ax_cv_cxxflags_gcc_option__ftrapv" >&5
 $as_echo "$ax_cv_cxxflags_gcc_option__ftrapv" >&6; }
 var=$ax_cv_cxxflags_gcc_option__ftrapv
+case ".$var" in
+     .ok|.ok,*)  ;;
+   .|.no|.no,*)  ;;
+   *)
+   if echo " $CXXFLAGS " | grep " $var " 2>&1 >/dev/null
+   then { { $as_echo "$as_me:${as_lineno-$LINENO}: : CXXFLAGS does contain \$var"; } >&5
+  (: CXXFLAGS does contain $var) 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }
+   else { { $as_echo "$as_me:${as_lineno-$LINENO}: : CXXFLAGS=\"\$CXXFLAGS \$var\""; } >&5
+  (: CXXFLAGS="$CXXFLAGS $var") 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }
+                      CXXFLAGS="$CXXFLAGS $var"
+   fi
+ ;;
+esac
+
+      { $as_echo "$as_me:${as_lineno-$LINENO}: checking CXXFLAGS for gcc -ftrack-macro-expansion" >&5
+$as_echo_n "checking CXXFLAGS for gcc -ftrack-macro-expansion... " >&6; }
+if ${ax_cv_cxxflags_gcc_option__ftrack_macro_expansion+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+  ax_cv_cxxflags_gcc_option__ftrack_macro_expansion="no, unknown"
+
+ ac_ext=cpp
+ac_cpp='$CXXCPP $CPPFLAGS'
+ac_compile='$CXX -c $CXXFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CXX -o conftest$ac_exeext $CXXFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_cxx_compiler_gnu
+
+ ac_save_CXXFLAGS="$CXXFLAGS"
+for ac_arg in "-pedantic -Werror % -ftrack-macro-expansion"     "-pedantic % -ftrack-macro-expansion %% no, obsolete"     #
+do CXXFLAGS="$ac_save_CXXFLAGS "`echo $ac_arg | sed -e 's,%%.*,,' -e 's,%,,'`
+   cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+int
+main ()
+{
+return 0;
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_cxx_try_compile "$LINENO"; then :
+  ax_cv_cxxflags_gcc_option__ftrack_macro_expansion=`echo $ac_arg | sed -e 's,.*% *,,'`; break
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+done
+ CXXFLAGS="$ac_save_CXXFLAGS"
+ ac_ext=cpp
+ac_cpp='$CXXCPP $CPPFLAGS'
+ac_compile='$CXX -c $CXXFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CXX -o conftest$ac_exeext $CXXFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_cxx_compiler_gnu
+
+
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ax_cv_cxxflags_gcc_option__ftrack_macro_expansion" >&5
+$as_echo "$ax_cv_cxxflags_gcc_option__ftrack_macro_expansion" >&6; }
+var=$ax_cv_cxxflags_gcc_option__ftrack_macro_expansion
 case ".$var" in
      .ok|.ok,*)  ;;
    .|.no|.no,*)  ;;

configure.ac

@@ -149,7 +149,8 @@ AS_IF([test "x$enable_warnings" = "xyes"],
 
 AS_CASE([$ax_cv_cxx_compiler_vendor],
   [gnu|clang],
-  [AS_IF([test "x$enable_warnings" = "xyes"],
+  [AX_CXXFLAGS_GCC_OPTION([-fdiagnostics-show-caret])
+   AS_IF([test "x$enable_warnings" = "xyes"],
      [AX_CXXFLAGS_GCC_OPTION([-Wextra])
       dnl The -ansi switch sets __STRICT_ANSI__ which disables some
       dnl useful function declarations in MinGW and Cygwin headers.
@@ -188,7 +189,8 @@ AS_CASE([$ax_cv_cxx_compiler_vendor],
          AX_CXXFLAGS_GCC_OPTION([-fstack-protector])])
       dnl -Wstack-protector results into not too interesting warnings.
       dnl AX_CXXFLAGS_GCC_OPTION([-Wstack-protector])
-      AX_CXXFLAGS_GCC_OPTION([-ftrapv])],
+      AX_CXXFLAGS_GCC_OPTION([-ftrapv])
+      AX_CXXFLAGS_GCC_OPTION([-ftrack-macro-expansion])],
      [AC_REQUIRE([AC_PROG_GREP])
       AS_IF([AS_ECHO_N(["$CXXFLAGS"]) dnl
              | $GREP -e ['\(^\|[[:space:]]\)-O\([^[:space:]]*\([[:space:]]\|$\)\)'] >/dev/null],