esac
done
+# If usethreads and clang, add -Wthread-safety for clang 3.5 or later.
+# gccversion is defined also for clang, because compat, use that for matching.
+# Apple overwrites clang version with XCode version.
+# Aggressively forward-proofing.
+case "$usethreads" in
+define)
+case "$gccversion" in
+*" Clang 3."[56789]*|*" Clang "[456]*|*"Apple LLVM "[6789]*)
+ for f in -Wthread-safety
+ do
+ case " $warn " in
+ *" $f "*) ;; # Skip if already there.
+ *)
+ echo "cflags.SH: Adding $f because usethreads and clang and gccversion '$gccversion'"
+ warn="$warn $f"
+ ;;
+ esac
+ done
+;;
+esac
+;;
+esac
+
echo "cflags.SH: cc = $cc"
echo "cflags.SH: ccflags = $ccflags"
echo "cflags.SH: stdflags = $stdflags"