configure checks for gcc options that clang does not support

Maybe they'll be supported somewhen in the future, so do not hardcode
them out. Also, gb_DEBUG_C(XX)FLAGS are apparently common GCC options,
not platform-specific.

config_host.mk.in

@@ -189,6 +189,11 @@ export GUI_FOR_BUILD=@GUI_FOR_BUILD@
 export GXX_INCLUDE_PATH=@GXX_INCLUDE_PATH@
 export HAVE_CXX0X=@HAVE_CXX0X@
 export HAVE_GCC_AVX=@HAVE_GCC_AVX@
+export HAVE_GCC_GGDB2=@HAVE_GCC_GGDB2@
+export HAVE_GCC_FINLINE_LIMIT=@HAVE_GCC_FINLINE_LIMIT@
+export HAVE_GCC_FNO_INLINE=@HAVE_GCC_FNO_INLINE@
+export HAVE_GCC_FNO_DEFAULT_INLINE=@HAVE_GCC_FNO_DEFAULT_INLINE@
+export HAVE_GCC_FNO_ENFORCE_EH_SPECS=@HAVE_GCC_FNO_ENFORCE_EH_SPECS@
 export HAVE_GCC_NO_LONG_DOUBLE=@HAVE_GCC_NO_LONG_DOUBLE@
 export HAVE_GCC_VISIBILITY_BROKEN=@HAVE_GCC_VISIBILITY_BROKEN@
 export HAVE_GCC_VISIBILITY_FEATURE=@HAVE_GCC_VISIBILITY_FEATURE@

configure.in

@@ -2540,6 +2540,10 @@ dnl ===================================================================
 dnl  Is it actually Clang?
 dnl ===================================================================
 
+COM_GCC_IS_CLANG=
+HAVE_GCC_GGDB2=
+HAVE_GCC_FINLINE_LIMIT=
+HAVE_GCC_FNO_INLINE=
 if test "$GCC" = "yes"; then
     AC_MSG_CHECKING([whether GCC is actually Clang])
     AC_COMPILE_IFELSE([AC_LANG_SOURCE([[
@@ -2551,8 +2555,48 @@ if test "$GCC" = "yes"; then
         [AC_MSG_RESULT([yes])
          COM_GCC_IS_CLANG=TRUE],
         [AC_MSG_RESULT([no])])
+
+    # check various GCC options that Clang does not support now but maybe
+    # will somewhen in the future, check them even for GCC, so that the flags
+    # are set
+
+    AC_MSG_CHECKING([whether $CC supports -ggdb2])
+    save_CFLAGS=$CFLAGS
+    CFLAGS="$CFLAGS -Werror -ggdb2"
+    AC_LINK_IFELSE([AC_LANG_PROGRAM([[]], [[ return 0; ]])],[ HAVE_GCC_GGDB2=TRUE ],[])
+    CFLAGS=$save_CFLAGS
+    if test "$HAVE_GCC_GGDB2" = "TRUE"; then
+        AC_MSG_RESULT([yes])
+    else
+        AC_MSG_RESULT([no])
+    fi
+
+    AC_MSG_CHECKING([whether $CC supports -finline-limit=0])
+    save_CFLAGS=$CFLAGS
+    CFLAGS="$CFLAGS -Werror -finline-limit=0"
+    AC_LINK_IFELSE([AC_LANG_PROGRAM([[]], [[ return 0; ]])],[ HAVE_GCC_FINLINE_LIMIT=TRUE ],[])
+    CFLAGS=$save_CFLAGS
+    if test "$HAVE_GCC_FINLINE_LIMIT" = "TRUE"; then
+        AC_MSG_RESULT([yes])
+    else
+        AC_MSG_RESULT([no])
+    fi
+
+    AC_MSG_CHECKING([whether $CC supports -fno-inline])
+    save_CFLAGS=$CFLAGS
+    CFLAGS="$CFLAGS -Werror -fno-inline"
+    AC_LINK_IFELSE([AC_LANG_PROGRAM([[]], [[ return 0; ]])],[ HAVE_GCC_FNO_INLINE=TRUE ],[])
+    CFLAGS=$save_CFLAGS
+    if test "$HAVE_GCC_FNO_INLINE" = "TRUE"; then
+        AC_MSG_RESULT([yes])
+    else
+        AC_MSG_RESULT([no])
+    fi
 fi
 AC_SUBST(COM_GCC_IS_CLANG)
+AC_SUBST(HAVE_GCC_GGDB2)
+AC_SUBST(HAVE_GCC_FINLINE_LIMIT)
+AC_SUBST(HAVE_GCC_FNO_INLINE)
 
 HAVE_LD_BSYMBOLIC_FUNCTIONS=
 if test "$GCC" = "yes"; then
@@ -4695,6 +4739,43 @@ fi
 
 AC_SUBST(HAVE_SFINAE_ANONYMOUS_BROKEN)
 
+dnl ===================================================================
+dnl  Clang++ tests
+dnl ===================================================================
+
+HAVE_GCC_FNO_DEFAULT_INLINE=
+HAVE_GCC_FNO_ENFORCE_EH_SPECS=
+if test "$GCC" = "yes"; then
+    AC_MSG_CHECKING([whether $CXX supports -fno-default-inline])
+    AC_LANG_PUSH([C++])
+    save_CXXFLAGS=$CXXFLAGS
+    CXXFLAGS="$CFLAGS -Werror -fno-default-inline"
+    AC_LINK_IFELSE([AC_LANG_PROGRAM([[]], [[ return 0; ]])],[ HAVE_GCC_FNO_DEFAULT_INLINE=TRUE ],[])
+    CXXFLAGS=$save_CXXFLAGS
+    AC_LANG_POP([C++])
+    if test "$HAVE_GCC_FNO_DEFAULT_INLINE" = "TRUE"; then
+        AC_MSG_RESULT([yes])
+    else
+        AC_MSG_RESULT([no])
+    fi
+
+    AC_MSG_CHECKING([whether $CXX supports -fno-enforce-eh-specs])
+    AC_LANG_PUSH([C++])
+    save_CXXFLAGS=$CXXFLAGS
+    CXXFLAGS="$CFLAGS -Werror -fno-enforce-eh-specs"
+    AC_LINK_IFELSE([AC_LANG_PROGRAM([[]], [[ return 0; ]])],[ HAVE_GCC_FNO_ENFORCE_EH_SPECS=TRUE ],[])
+    CXXFLAGS=$save_CXXFLAGS
+    AC_LANG_POP([C++])
+    if test "$HAVE_GCC_FNO_ENFORCE_EH_SPECS" = "TRUE"; then
+        AC_MSG_RESULT([yes])
+    else
+        AC_MSG_RESULT([no])
+    fi
+fi
+AC_SUBST(HAVE_GCC_FNO_DEFAULT_INLINE)
+AC_SUBST(HAVE_GCC_FNO_ENFORCE_EH_SPECS)
+
+
 dnl ===================================================================
 dnl allocator
 dnl ===================================================================

solenv/gbuild/platform/WNT_INTEL_GCC.mk

@@ -106,16 +106,6 @@ ifeq ($(MINGW_GCCLIB_EH),YES)
 gb_LinkTarget_LDFLAGS += -shared-libgcc
 endif
 
-# clang does not know -ggdb2
-ifneq ($(COM_GCC_IS_CLANG),TRUE)
-GGDB2=-ggdb2
-else
-GGDB2=-g2
-endif
-
-gb_DEBUG_CFLAGS := $(GGDB2) -finline-limit=0 -fno-inline
-gb_DEBUG_CXXFLAGS := -fno-default-inline
-
 gb_STDLIBS := \
 	mingwthrd \
 	mingw32 \

solenv/gbuild/platform/com_GCC_defs.mk

@@ -93,7 +93,7 @@ gb_LinkTarget_EXCEPTIONFLAGS := \
 
 ifeq ($(gb_PRODUCT),$(true))
 # Clang doesn't have this option
-ifneq ($(COM_GCC_IS_CLANG),TRUE)
+ifeq ($(HAVE_GCC_FNO_ENFORCE_EH_SPECS),TRUE)
 gb_LinkTarget_EXCEPTIONFLAGS += \
 	-fno-enforce-eh-specs
 endif
@@ -112,6 +112,29 @@ gb_COMPILEROPTFLAGS := $(gb_COMPILERDEFAULTOPTFLAGS)
 endif
 gb_COMPILERNOOPTFLAGS := -O0
 
+# Clang does not know -ggdb2 or some other options
+ifeq ($(HAVE_GCC_GGDB2),TRUE)
+GGDB2=-ggdb2
+else
+GGDB2=-g2
+endif
+
+ifeq ($(HAVE_GCC_FINLINE_LIMIT),TRUE)
+FINLINE_LIMIT0=-finline-limit=0
+endif
+
+ifeq ($(HAVE_GCC_FNO_INLINE),TRUE)
+FNO_INLINE=-fno-inline
+endif
+
+ifeq ($(HAVE_GCC_FNO_DEFAULT_INLINE),TRUE)
+FNO_DEFAULT_INLINE=-fno-default-inline
+endif
+
+gb_DEBUG_CFLAGS := $(GGDB2) $(FINLINE_LIMIT0) $(FNO_INLINE)
+gb_DEBUG_CXXFLAGS := $(FNO_DEFAULT_INLINE)
+
+
 gb_LinkTarget_INCLUDE := $(filter-out %/stl, $(subst -I. , ,$(SOLARINC)))
 gb_LinkTarget_INCLUDE_STL := $(filter %/stl, $(subst -I. , ,$(SOLARINC)))
 

solenv/gbuild/platform/unxgcc.mk

@@ -181,16 +181,6 @@ gb_COMPILEROPTFLAGS := $(gb_COMPILERDEFAULTOPTFLAGS)
 gb_LINKEROPTFLAGS := -Wl,-O1
 endif
 
-# clang does not know -ggdb2
-ifneq ($(COM_GCC_IS_CLANG),TRUE)
-GGDB2=-ggdb2
-else
-GGDB2=-g2
-endif
-
-gb_DEBUG_CFLAGS := $(GGDB2) -finline-limit=0 -fno-inline
-gb_DEBUG_CXXFLAGS := -fno-default-inline
-
 gb_COMPILERNOOPTFLAGS := -O0
 
 # LinkTarget class