Use -Wextra (facebook#807)

Summary:
Pull Request resolved: facebook#807

See what happens on CircleCI.

Reviewed By: ssj933

Differential Revision: D47281033

fbshipit-source-id: 0c7853f2895035d984c63c0c45d2ac910b7162a3

Makefile.am

@@ -28,20 +28,25 @@ DISABLED_WARNINGS = \
   -Wno-invalid-offsetof \
   -Wno-maybe-uninitialized \
   -Wno-parentheses \
+  -Wno-range-loop-analysis \
+  -Wno-redundant-move \
   -Wno-return-type \
   -Wno-shift-count-overflow \
   -Wno-sign-compare \
   -Wno-strict-aliasing \
   -Wno-stringop-overflow \
   -Wno-stringop-overread \
+  -Wno-type-limits \
   -Wno-uninitialized \
   -Wno-unused-but-set-variable \
   -Wno-unused-function \
+  -Wno-unused-parameter \
   -Wno-unused-private-field \
   -Wno-unused-result \
+  -Wno-unused-value \
   -Wno-unused-variable
 
-AM_CXXFLAGS = --std=gnu++17 -O3 -Wall -Werror $(DISABLED_WARNINGS) -g
+AM_CXXFLAGS = --std=gnu++17 -O3 -Wall -Werror -Wextra $(DISABLED_WARNINGS) -g
 
 include $(top_srcdir)/Makefile.inc
 

libresource/android-base/macros.h

@@ -9,7 +9,7 @@
 #define _FB_MACROS_REIMPLEMENTATION
 
 #ifndef FALLTHROUGH_INTENDED
-#define FALLTHROUGH_INTENDED [[clang::fallthrough]]
+#define FALLTHROUGH_INTENDED [[fallthrough]]
 #endif
 
 #endif // _FB_MACROS_REIMPLEMENTATION