Turn off compiler all warnings to avoid compilation failures

Summary: public
-Wno-error flag doesn't turn off errors which were turned on using -Werror=$WARN_TYPE.
In order to turn these off we'd have to add -Wno-error=$WARN_TYPE for each warning type.
So instead, turn off all warnings so they can't get elevated to error

Reviewed By: jvillard

Differential Revision: D2690810

fb-gh-sync-id: 7d6611f

infer/lib/clang_wrappers/clang_wrapper

@@ -35,6 +35,8 @@ done
 
 # Never error on warnings. Clang is often more strict than Apple's version.
 # These arguments are appended to override previous opposite settings.
-COMMAND+=("-Wno-error" "-Qunused-arguments")
+# How it's done: surpress all the warnings, since there are no warnings,
+# compiler can't elevate them to error level.
+COMMAND+=("-Wno-everything")
 
 "${COMMAND[@]}"

infer/tests/codetoanalyze/objc/errors/category_procdesc/main.c

@@ -8,7 +8,7 @@
 */
 
 #import "EOCPerson.h"
-#include <stdlib.h>
+
 
 int main() {
     EOCPerson *person = [[EOCPerson alloc] init];