一个宏替换问题

Question

#include <stdio.h>

#define AMP_Assert( expr ) if( !(expr) ) { \
    printf("** Assertion failed: \"" #expr "\" at %s:%d %s()\n", __FILE__, __LINE__, __FUNCTION__);\
    }

int main(int argc, const char* argv[])
{
    int a = 1;
    AMP_Assert(a % 8 == 0);
    return 0;
}

以下警告将在gcc和msvc中发生

macrotest.cpp: In function ‘int main(int, const char**)’:
macrotest.cpp:4:95: warning: unknown conversion type character ‘ ’ in format [-Wformat=]

如何摆脱这种警告？让宏替换'％'正确替换。