Re: GCov and GCC, *.da Files Not Created

[Andi Hellmund <mail at andihellmund dot com>]

Hey Ryan,
> I tried changing the location to which the data files are written by
> setting the GCOV_PREFIX environment variable before building my
> executable.  After rebuilding, I saw that the location to which the
> suite1.da file would be written did not change.
This GCOV_PREFIX will - in newer versions at least - have no impact on 
the compile-time behavior. This environment variable is just used at 
run-time to instruct libgcov where to put the data files.

> I checked the GCC 3.3.6
> manual, and saw that the section about "Data file relocation to support
> cross-profiling" does not exist.  Was support for the GCOV_PREFIX and
> GCOV_PREFIX_STRIP environment variables added sometime after 3.3.6?
>    
I shortly looked through the GCC manuals and it seems that this feature 
was added with 4.1.2. But anyway, independent of this feature, you 
should get the data files at least at the embedded location.
> I also ensured that I had write access to the "src" directory, but the
> suite1.da file is still not getting created.  Do you have any other
> suggestions that I might be able to try?
>    
Here's what I would try:

* if possible in your project, try a newer version; the most recent 
version is 4.5.1
* debug the gcc runtime library; the parts responsible for data file 
creation are contained in libgcc (e.g. libgcc.a)
   the source function doing the file creation is __bb_exit_func 
(libgcc2.c)

BTW, whenever the GCOV part in 3.3.6 cannot open the data file, it would 
print out an error message to stderr like

arc profiling: Can't open output file 
/devel/gcc/build-3.3.6/gcc/test/test.da.

Did you see this error message somewhere? Maybe in a re-directed logfile?


Andi