Re: [boost] Compiler Warnings Tests

Subject: Re: [boost] Compiler Warnings Tests
From: Robert Ramey (ramey_at_[hidden])
Date: 2009-11-27 13:45:23

Paul A. Bristow wrote:
> And I'm starting a new thread for Compiler Warnings Tests
>
> The Microsoft docs examples might be a good start?
>
> // C4244_level4.cpp
> // compile with: /W4  == actually warnings = all
>
> (warnings = errors will allow normal fail testing if it isn;t
> possible to check for warnings?)
>
> //  AND MS extensions off?
>
> int aa;
> unsigned short bb;
>
> int main() {
>   int b = 0, c = 0;
>   short a = b + c;   // C4244
>
>   bb += c;   // C4244
>   bb = bb + c;   // C4244
>   bb += static_cast<unsigned short>(aa);   // C4244
>   bb = bb + static_cast<unsigned short>(aa);   // OK
> }
>
> So are you proposing a collection of these, with versions that should
> compile and others that should not, for example:
>
> int main()
> {
>   int b = 0, c = 0;
>  short a =  b + c; // C4244
> }
>
> and another with
>
> int main()
> {
>   int b = 0, c = 0;
>  short a =  static_cast<short>(b + c); // OK - NO C4244
> }
>
> all run by a jamfile.v2.
>
> Or am I still misunderstanding you?

You've got it.

The only difference would be that the warning shouldn't be associated with a 
particular compiler.

Look at boost/libs/config tests for inspiriation.  Tests would be something 
like:

boost/libs/warnings/
    test_data_truncation
        // this would correspond to C4244 for ms and ? for other ones
        // this test would be "compile-pass"
        // and it would contain a number of tests cases

    test_unused_argument
    test_argument_name_shadowing
    test_virtual_dtor_missing
    test_cant_create_default_construtor
    test_cant_create_default_assignment
    ...

On the boost testing matrix, the first row describes the environment.
To make this useful, this test should be run with the first row -
environment description including the warning level.

Note that I use my library_test.sh to run tests for one specific
library.  This creates an html test matrix on your local machine
which shows all the warning emitted.  The beauty of this
system is that it's very easy to run the tests and create the
test matrix on your local machine for just one library.

Robert Ramey