Check if compiler accepts -Wno-missing-field-initializers.

Use it for nsas build even if not GCC.
(It was already used by default for nsas for past few days,
but that breaks old GCC. This will fix build for Solaris GCC.)


git-svn-id: svn://bind10.isc.org/svn/bind10/trunk@3877 e5f2f494-b856-4b98-b285-d166d9295462

configure.ac

@@ -195,6 +195,19 @@ fi
 # specify the default warning flags in CXXFLAGS and let specific modules
 # "override" the default.
 
+# This may be used to try compiler flags.
+AC_DEFUN([BIND10_CXX_TRY_FLAG], [
+  AC_MSG_CHECKING([whether $CXX supports $1])
+
+  bind10_save_CXXFLAGS="$CXXFLAGS"
+  CXXFLAGS="$CXXFLAGS $1"
+
+  AC_COMPILE_IFELSE([ ], [bind10_cxx_flag=yes], [bind10_cxx_flag=no])
+  CXXFLAGS="$bind10_save_CXXFLAGS"
+
+  AC_MSG_RESULT([$bind10_cxx_flag])
+])
+
 werror_ok=0
 
 # SunStudio compiler requires special compiler options for boost
@@ -204,6 +217,10 @@ CXXFLAGS="$CXXFLAGS -library=stlport4 -features=tmplife -features=tmplrefstatic"
 MULTITHREADING_FLAG="-mt"
 fi
 
+BIND10_CXX_TRY_FLAG(-Wno-missing-field-initializers,
+	[WARNING_NO_MISSING_FIELD_INITIALIZERS_CFLAG="-Wno-missing-field-initializers"])
+AC_SUBST(WARNING_NO_MISSING_FIELD_INITIALIZERS_CFLAG)
+
 # gcc specific settings:
 if test "X$GXX" = "Xyes"; then
 B10_CXXFLAGS="-Wall -Wextra -Wwrite-strings -Woverloaded-virtual -Wno-sign-compare"

src/lib/nsas/Makefile.am

@@ -7,12 +7,11 @@ AM_CPPFLAGS += -I$(top_srcdir)/src/lib/nsas -I$(top_builddir)/src/lib/nsas
 AM_CPPFLAGS += $(SQLITE_CFLAGS)
 AM_CXXFLAGS = $(B10_CXXFLAGS)
 
-if USE_GXX
 # Some versions of GCC warn about some versions of Boost regarding
 # missing initializer for members in its posix_time.
 # https://svn.boost.org/trac/boost/ticket/3477
-AM_CXXFLAGS += -Wno-missing-field-initializers
-endif
+# But older GCC compilers don't have the flag.
+AM_CXXFLAGS += $(WARNING_NO_MISSING_FIELD_INITIALIZERS_CFLAG)
 
 if USE_CLANGPP
 # clang++ complains about unused function parameters in some boost header

src/lib/nsas/tests/Makefile.am

@@ -11,12 +11,11 @@ if USE_STATIC_LINK
 AM_LDFLAGS += -static
 endif
 
-if USE_GXX
 # Some versions of GCC warn about some versions of Boost regarding
 # missing initializer for members in its posix_time.
 # https://svn.boost.org/trac/boost/ticket/3477
-AM_CXXFLAGS += -Wno-missing-field-initializers
-endif
+# But older GCC compilers don't have the flag.     
+AM_CXXFLAGS += $(WARNING_NO_MISSING_FIELD_INITIALIZERS_CFLAG)
 
 if USE_CLANGPP
 # see ../Makefile.am