configure: detect compiler flag

Use m4 macro AC_TRY_CCFLAG to detect presence of some compiler
option.
Use it to detect -Wjump-misses-init.

acinclude.m4

@@ -0,0 +1,39 @@
+dnl AC_GCC_VERSION
+dnl check for compiler version
+dnl sets COMPILER_VERSION and GCC_VERSION
+
+AC_DEFUN([AC_CC_VERSION],
+[
+ AC_MSG_CHECKING([C compiler version])
+ COMPILER_VERSION=`$CC -v 2>&1 | grep version`
+ case "$COMPILER_VERSION" in
+ *gcc*)
+ dnl Ok, how to turn $3 into the real $3
+ GCC_VERSION=`echo $COMPILER_VERSION | \
+ sed -e 's/[[^ ]]*\ [[^ ]]*\ \([[^ ]]*\)\ .*/\1/'` ;;
+ *) GCC_VERSION=unknown ;;
+ esac
+ AC_MSG_RESULT($GCC_VERSION)
+])
+
+dnl AC_TRY_CCFLAG([CCFLAG], [VAR], [ACTION-IF-WORKS], [ACTION-IF-FAILS])
+dnl check if $CC supports a given flag
+
+AC_DEFUN([AC_TRY_CCFLAG],
+[
+ AC_REQUIRE([AC_PROG_CC])
+ ac_save_CFLAGS=$CFLAGS
+ CFLAGS=$1
+ AC_MSG_RESULT([KOUKEJ $name])
+ AC_CACHE_CHECK([whether $CC accepts $1 flag], [ac_cv_flag_$2],
+ [AC_COMPILE_IFELSE([AC_LANG_PROGRAM()],
+ [AS_VAR_SET([ac_cv_flag_$2], [yes])],
+ [AS_VAR_SET([ac_cv_flag_$2], [no])])])
+ CFLAGS=$ac_save_CFLAGS
+ $2=AS_VAR_GET([ac_cv_flag_$2])
+ if test "$2" = yes; then
+ ifelse([$3], [], [:], [$3])
+ else
+ ifelse([$4], [], [:], [$4])
+ fi
+])

aclocal.m4

@@ -169,3 +169,4 @@ else
 fi[]dnl
 ])# PKG_CHECK_MODULES
 
+m4_include([acinclude.m4])

configure

@@ -708,6 +708,7 @@ CUNIT_CFLAGS
 GENPNG
 GENHTML
 LCOV
+HAVE_WJUMP
 SACKPT_LIBS
 SACKPT_CFLAGS
 DLM_LIBS
@@ -8677,6 +8678,47 @@ else
  CSCOPE_CMD=
 fi
 
+
+
+ ac_save_CFLAGS=$CFLAGS
+ CFLAGS=-Wjump-misses-init
+ { $as_echo "$as_me:${as_lineno-$LINENO}: result: KOUKEJ $name" >&5
+$as_echo "KOUKEJ $name" >&6; }
+ { $as_echo "$as_me:${as_lineno-$LINENO}: checking whether $CC accepts -Wjump-misses-init flag" >&5
+$as_echo_n "checking whether $CC accepts -Wjump-misses-init flag... " >&6; }
+if test "${ac_cv_flag_HAVE_WJUMP+set}" = set; then :
+ $as_echo_n "(cached) " >&6
+else
+ cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h. */
+
+int
+main ()
+{
+
+ ;
+ return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+ ac_cv_flag_HAVE_WJUMP=yes
+else
+ ac_cv_flag_HAVE_WJUMP=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_flag_HAVE_WJUMP" >&5
+$as_echo "$ac_cv_flag_HAVE_WJUMP" >&6; }
+ CFLAGS=$ac_save_CFLAGS
+ HAVE_WJUMP=$ac_cv_flag_HAVE_WJUMP
+ if test "HAVE_WJUMP" = yes; then
+ :
+ else
+ :
+ fi
+
+
+
 ################################################################################
 { $as_echo "$as_me:${as_lineno-$LINENO}: checking for C optimisation flag" >&5
 $as_echo_n "checking for C optimisation flag... " >&6; }

configure.in

@@ -835,6 +835,10 @@ else
  CSCOPE_CMD=
 fi
 
+dnl -- Check if compiler supports -Wjump-misses-init
+AC_TRY_CCFLAG([-Wjump-misses-init], [HAVE_WJUMP], [], [])
+AC_SUBST(HAVE_WJUMP)
+
 ################################################################################
 dnl -- Override optimisation
 AC_MSG_CHECKING(for C optimisation flag)

make.tmpl.in

@@ -138,9 +138,13 @@ WFLAGS += -Wall -Wundef -Wshadow -Wcast-align -Wwrite-strings \
  -Wpointer-arith -Wclobbered -Wempty-body -Wignored-qualifiers \
  -Wmissing-parameter-type -Wold-style-declaration -Woverride-init \
  -Wtype-limits -Wuninitialized -Wmissing-include-dirs -Wsync-nand \
- -Wfloat-equal -Wjump-misses-init -Wlogical-op -Wstrict-prototypes \
+ -Wfloat-equal -Wlogical-op -Wstrict-prototypes \
  -Wold-style-definition -Wmissing-format-attribute
 
+ifeq ("@HAVE_WJUMP@", "yes")
+WFLAGS += -Wjump-misses-init
+endif
+
 #WFLAGS += -W -Wno-sign-compare -Wno-unused-parameter -Wno-missing-field-initializers
 #WFLAGS += -Wsign-compare -Wunused-parameter -Wmissing-field-initializers 
 #WFLAGS += -Wconversion -Wbad-function-cast -Wcast-qual -Waggregate-return -Wpacked