Merge branch 'jk/use-wunreachable-code-for-devs' into next

* jk/use-wunreachable-code-for-devs:
  config.mak.dev: enable -Wunreachable-code

Author: gitster

config.mak.dev

@@ -39,6 +39,7 @@ DEVELOPER_CFLAGS += -Wunused
 DEVELOPER_CFLAGS += -Wvla
 DEVELOPER_CFLAGS += -Wwrite-strings
 DEVELOPER_CFLAGS += -fno-common
+DEVELOPER_CFLAGS += -Wunreachable-code
 
 ifneq ($(filter clang4,$(COMPILER_FEATURES)),)
 DEVELOPER_CFLAGS += -Wtautological-constant-out-of-range-compare