remove GCC specifc optimization

Makefile

@@ -2,7 +2,7 @@
 CFLAGS += -ansi -pedantic-errors -Werror=pedantic -fno-asm -fno-common
 
 # Optimization
-CFLAGS += -O3 -fipa-pta
+CFLAGS += -O3
 
 # Additional warnings
 CFLAGS += -Wall -Wextra