Linux GCC compilation error (reprint)

Transferred from: http://www.linuxidc.com/Linux/2012-01/52153.htm

C programming under Linux is different from Windows, if you are using GCC to compile code with the hint ' for ' loop initial declarations is only allowed in C99 mode, Maybe it's because you're using an undefined variable in the loop loop like for, like:

for (int i=0;i<10;i++)

{

}

This kind of writing in VC is not wrong, and sub-GCC will prompt error, requirements to comply with C89 standards, C89 standard is not supported by the above-mentioned notation. If you have to write like this, you can compile this, using the C99 standard:

GCC Helo.c-std=c99-o Hello

Of course, you can also define the I variable first.

int i;

for (i=0;i<10;i++)

{

}

This will not prompt the ' for ' loop initial declarations is only allowed in C99 mode such a mistake

Linux GCC compilation error (reprint)