File line/column mapping is wrong

[paulross]

There are some xfailing tests in tests/unit/test_core/test_FileLocation.py that illustrate the problem. The remedy is being worked on the fileLineColumn branch.

[SourceCodeDeleted]

Was any progress made here?

[BengtGustafsson]

I'd be very interested in fixing this. We've spent many hours over the years trying to figure out which line errors actually pertain to. We use CPIP to preprocess before calling the hlsl and opencl compilers.

My observation is that if a macro #define has an empty line after it the #define line does not create an empty line in the output token stream which causes subsequent line numbers to be off. This of course accumulates as more macros are defined.

[BengtGustafsson]

I digged a bit deeper and there is also problems with #if/#else so that the lines that are in the false branch are not getting replaced with empty lines, causing larger line number diffs.

#ifdef D3D
// HLSL leaves max on NaN undefined, while OpenCL defines fmax to return the non-NaN argument if
// either argument is NaN. Only the first argument is allowed to be NaN in this wrapper.
float safe_fmax(float xnan, float y)
{
    return isnan(xnan) ? y : max(xnan, y);
}
#else
#define safe_fmax fmax
#endif

This 10 line snippet produces only 2 empty lines if D3D is not defined and 7 lines including the safe_fmax function definition if it is defined.

[BengtGustafsson]

Furthermore a #pragma generates two additional # line file lines in the output. This is usually ok but if you put a // comment after the pragma the succeeding # is not in the first column. This is hard to handle as # not in the first column could be a stringize pp-operator. We just removed the comment, but anyhow.

Question: Why did you change the output #line directives to just # characters. We had an old version before and how we had to replace \n# with \n#line and remove any trailing ints to get it through the succeding hlsl and opencl compilers.