(需要 std::format 为 constexpr):static_assert(sizeof(long)==4,std::format("期待 4,得到 {}", sizeof(long)));#endifintmain(){inta, b;swap(a, b);no_copy nc_a, nc_b;swap(nc_a, nc_b);// 1[[maybe_unused]]data_structure<int>ds_ok;[[maybe_unused]]data_structure<no_...
背景: muduo网络库中的如下用法: 1static_assert(sizeof(InetAddress) ==sizeof(structsockaddr_in6),2"InetAddress is same size as sockaddr_in6");3static_assert(offsetof(sockaddr_in, sin_family) ==0,"sin_family offset 0");4static_assert(offsetof(sockaddr_in6, sin6_family) ==0,"sin6_fam...
"int must be 4 bytes");static_assert(sizeof(std::int64_t)==8,"64-bit integer must be 8 ...
static_assert(sizeof(void *) == 4, "64-bit code generation is not supported."); 该static_assert用来确保编译仅在32位的平台上进行,不支持64位的平台,该语句可以放在文件的开头处,这样可以尽早检查,以节省失败情况下的编译时间。 我们知道,C++现有的标准中,就有assert、#error两个设施,也是用来检查错误...
BOOST_STATIC_ASSERT(sizeof(int) * CHAR_BIT >= 32); BOOST_STATIC_ASSERT(WCHAR_MIN >= 0); } // namespace my_conditions 1. 2. 3. 4. 确保int类型至少32位,wchar_t类型为unsigned。 也可以在模板函数中检测入口参数的类型是否符合要求
static_assert(sizeof(T) >= 4, "T must be at least 4 bytes"); } }; 在上述示例中,static_assert用于检查模板参数T的大小是否至少为4个字节。如果T的大小小于4个字节,编译时将会产生一个错误,并显示错误消息"T must be at least 4 bytes"。
static_assert(sizeof(long) == 4, "错误, 不是32位平台..."); cout << "64bit Linux 指针大小: " << sizeof(char*) << endl; cout << "64bit Linux long 大小: " << sizeof(long) << endl; return 0; } 1. 2. 3. 4.
如果这真的更好，你将不得不决定，这也取决于编译器。它还使你能够隐藏预期的大小与模板Map，以总结...
// crt__static_assert.c#include<crtdbg.h>#include<stdio.h>_STATIC_ASSERT(sizeof(int) >=2); _STATIC_ASSERT(sizeof(long) ==1);// C2466intmain(){printf("I am sure that sizeof(int) will be >= 2: %d\n",sizeof(int));printf("I am not so sure that sizeof(long) == 1: %d...
{ assert(b!=0);//断言returna /b; }intmain1() { cout<< divv(1,0) <<endl; cin.get(); } 2.静态断言(static_assert) static_assert(sizeof(void*) ==8,"is not 64, baby");intmain() {//int b = 0;constinta =0;//static_assert(a > 0, "is not 64, baby");//变量不可...