C++ – Selectively disable GCC warnings for only part of a translation unit

ccompiler-warningsgccpragma

What's the closest GCC equivalent to this MSVC preprocessor code?

#pragma warning( push )                    // Save the current warning state.
#pragma warning( disable : 4723 )          // C4723: potential divide by 0
// Code which would generate warning 4723.
#pragma warning( pop )                     // Restore warnings to previous state.

We have code in commonly included headers which we do not want to generate a specific warning. However we want files which include those headers to continue to generate that warning (if the project has that warning enabled).

Best Answer

This is possible in GCC since version 4.6, or around June 2010 in the trunk.

Here's an example:

#pragma GCC diagnostic push
#pragma GCC diagnostic error "-Wuninitialized"
    foo(a);         /* error is given for this one */
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wuninitialized"
    foo(b);         /* no diagnostic for this one */
#pragma GCC diagnostic pop
    foo(c);         /* error is given for this one */
#pragma GCC diagnostic pop
    foo(d);         /* depends on command line options */

Related Solutions

C++ – How to get rid of `deprecated conversion from string constant to ‘char*’` warnings in GCC

Any functions into which you pass string literals "I am a string literal" should use char const * as the type instead of char*.

If you're going to fix something, fix it right.

Explanation:

You can not use string literals to initialise strings that will be modified, because they are of type const char*. Casting away the constness to later modify them is undefined behaviour, so you have to copy your const char* strings char by char into dynamically allocated char* strings in order to modify them.

Example:

#include <iostream>

void print(char* ch);

void print(const char* ch) {
    std::cout<<ch;
}

int main() {
    print("Hello");
    return 0;
}

Disable all gcc warnings

-w is the GCC-wide option to disable warning messages.

Best Answer

Related Solutions

C++ – How to get rid of `deprecated conversion from string constant to ‘char*’` warnings in GCC

Disable all gcc warnings

Related Topic