Add -Wunused-variable to warnings.m4

[deliverable/binutils-gdb.git] / gdb / gdbserver / configure

diff --git a/gdb/gdbserver/configure b/gdb/gdbserver/configure
index 6064a1eb10f469aad0f772e639f7cb1e4b22fc94..043bc216e43ca0f7b2ae90ef7990062036f75d62 100755 (executable)
--- a/gdb/gdbserver/configure
+++ b/gdb/gdbserver/configure
@@ -7237,7 +7237,7 @@ fi
 
 # The options we'll try to enable.
 build_warnings="-Wall -Wpointer-arith \
--Wno-unused -Wunused-value -Wunused-function \
+-Wno-unused -Wunused-value -Wunused-variable -Wunused-function \
 -Wno-switch -Wno-char-subscripts \
 -Wempty-body -Wunused-but-set-parameter -Wunused-but-set-variable \
 -Wno-sign-compare -Wno-narrowing -Wno-error=maybe-uninitialized \
@@ -7326,7 +7326,30 @@ $as_echo_n "checking compiler warning flags... " >&6; }
            CFLAGS="$CFLAGS -Werror $wtest"
            saved_CXXFLAGS="$CXXFLAGS"
            CXXFLAGS="$CXXFLAGS -Werror $wtest"
-           cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+           if test "x$w" = "x-Wunused-variable"; then
+             # Check for https://gcc.gnu.org/bugzilla/show_bug.cgi?id=38958,
+             # fixed in GCC 4.9.  This test is derived from the gdb
+             # source code that triggered this bug in GCC.
+             cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+struct scoped_restore_base {};
+                 struct scoped_restore_tmpl : public scoped_restore_base {
+                  ~scoped_restore_tmpl() {}
+                };
+int
+main ()
+{
+const scoped_restore_base &b = scoped_restore_tmpl();
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_cxx_try_compile "$LINENO"; then :
+  WARN_CFLAGS="${WARN_CFLAGS} $w"
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+           else
+             cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
 
 int
@@ -7341,6 +7364,7 @@ if ac_fn_cxx_try_compile "$LINENO"; then :
   WARN_CFLAGS="${WARN_CFLAGS} $w"
 fi
 rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+           fi
            CFLAGS="$saved_CFLAGS"
            CXXFLAGS="$saved_CXXFLAGS"
        esac