gcc-you can use this code to learn something about gcc, and inquire further into linux,
源代码在线查看： if-sc.c
/* Copyright (C) 2000 Free Software Foundation, Inc. */ /* { dg-do preprocess } */ /* Test that all operators correctly short circuit. */ #if (2 || 3 / 0) != 1 #error /* { dg-bogus "error" "|| short circuit" } */ #endif #if 0 && 3 / 0 #error /* { dg-bogus "error" "&& short circuit" } */ #endif #if 1 ? 0 : 3 / 0 #error /* { dg-bogus "error" "? : right short circuit" } */ #endif #if 0 ? 3 / 0 : 2 #else #error /* { dg-bogus "error" "? : left short circuit" } */ #endif #if -1 ? 0 && 3 / 0 : 3 / 0 + 5 == 5 #error /* { dg-bogus "error" "nested short circuiting" } */ #endif
