+2016-02-13 Mark Wielaard <mjw@redhat.com>
+
+ * configure.ac: Add check for whether gcc accepts -Wnull-dereference.
+
2016-02-08 Mark Wielaard <mjw@redhat.com>
* configure.ac: Add checks for sane -Wlogical-op and whether gcc
+2016-02-13 Mark Wielaard <mjw@redhat.com>
+
+ * eu.am: Check HAVE_NULL_DEREFERENCE_WARNING.
+ (AM_CFLAGS): Add NULL_DEREFERENCE_WARNING.
+
2016-02-09 Mark Wielaard <mjw@redhat.com>
* eu.am: Check SANE_LOGICAL_OP_WARNING and
DUPLICATED_COND_WARNING=
endif
+if HAVE_NULL_DEREFERENCE_WARNING
+NULL_DEREFERENCE_WARNING=-Wnull-dereference
+else
+NULL_DEREFERENCE_WARNING=
+endif
+
AM_CFLAGS = -std=gnu99 -Wall -Wshadow -Wformat=2 \
-Wold-style-definition -Wstrict-prototypes \
$(LOGICAL_OP_WARNING) $(DUPLICATED_COND_WARNING) \
+ $(NULL_DEREFERENCE_WARNING) \
$(if $($(*F)_no_Werror),,-Werror) \
$(if $($(*F)_no_Wunused),,-Wunused -Wextra) \
$(if $($(*F)_no_Wstack_usage),,$(STACK_USAGE_WARNING)) \
AM_CONDITIONAL(HAVE_DUPLICATED_COND_WARNING,
[test "x$ac_cv_duplicated_cond" != "xno"])
+# -Wnull-dereference was added by GCC6
+AC_CACHE_CHECK([whether gcc accepts -Wnull-dereference], ac_cv_null_dereference, [dnl
+old_CFLAGS="$CFLAGS"
+CFLAGS="$CFLAGS -Wnull-dereference"
+AC_COMPILE_IFELSE([AC_LANG_SOURCE([])],
+ ac_cv_null_dereference=yes, ac_cv_null_dereference=no)
+CFLAGS="$old_CFLAGS"])
+AM_CONDITIONAL(HAVE_NULL_DEREFERENCE_WARNING,
+ [test "x$ac_cv_null_dereference" != "xno"])
+
dnl Check if we have argp available from our libc
AC_LINK_IFELSE(
[AC_LANG_PROGRAM(