Remove unreachable code to make -Wunreachable-code on clang useful.

Makefile

@@ -12,7 +12,15 @@ else
 	CFLAGS_EXTRA=-O2
 endif
 
-CCFLAGS=-D_GNU_SOURCE=1 -Wall -Wextra -Werror-implicit-function-declaration -Wstrict-prototypes -Wno-missing-field-initializers $(CFLAGS_EXTRA) $(CFLAGS)
+# The -Wunreachable-code warning is only implemented in clang, but it
+# doesn't break anything for gcc to see it.
+WARNINGS=-Wall \
+				 -Wextra \
+				 -Werror-implicit-function-declaration \
+				 -Wstrict-prototypes \
+				 -Wno-missing-field-initializers \
+				 -Wunreachable-code
+CCFLAGS=-D_GNU_SOURCE=1 $(WARNINGS) $(CFLAGS_EXTRA) $(CFLAGS)
 LLDFLAGS=-lrt -lev $(LDFLAGS_EXTRA) $(LDFLAGS)
 
 CC?=gcc