+# We want no optimization, as they uncover warnings (therefore,
+# failures) about uninitialized variables in the test suite. FIXME:
+# fix the warnings, not the flags.
+ O0CFLAGS=`echo '@CFLAGS@' | sed 's/-O[0-9s] *//g'`
+O0CXXFLAGS=`echo '@CXXFLAGS@' | sed 's/-O[0-9s] *//g'`
+
+# Sometimes a test group needs to ignore gcc warnings, so it locally
+# sets CFLAGS to this.
+ NO_WERROR_CFLAGS="$O0CFLAGS @WARN_CFLAGS@ @WARN_CFLAGS_TEST@"
+NO_WERROR_CXXFLAGS="$O0CXXFLAGS @WARN_CXXFLAGS@ @WARN_CXXFLAGS_TEST@"
+
+# But most of the time, we want -Werror.
+ CFLAGS="$NO_WERROR_CFLAGS @WERROR_CFLAGS@"
+CXXFLAGS="$NO_WERROR_CXXFLAGS @WERROR_CXXFLAGS@"