Analysis of g++.dg/bprob/g++-bprob-1.C multilib failures

["Kaveh R. Ghazi" <ghazi at caip dot rutgers dot edu>]

On the 3.3. and 3.4 branches, I've noticed that
g++.dg/bprob/g++-bprob-1.C fails compilation when running multilib
passes.  E.g.:

http://gcc.gnu.org/ml/gcc-testresults/2002-12/msg00753.html
http://gcc.gnu.org/ml/gcc-testresults/2002-12/msg01074.html

It doesn't appear to be related to which particular multilib flag is
used, rather the first pass always succeeds and the second and all
subsequent ones fail.  Note here that one irix6.5 report starts with
-mabi=64 first and the other has it last.  In both cases whatever pass
goes first works.

http://gcc.gnu.org/ml/gcc-testresults/2002-12/msg00904.html
http://gcc.gnu.org/ml/gcc-testresults/2002-12/msg01108.html

Given this I believe it is a testsuite bug rather than a gcc bug.  I
looked in the log file to see what the compilation problem was and I
saw this output from the compilation:

 > g++: : No such file or directory
 > g++: : No such file or directory
 > compiler exited with status 1

Though it doesn't say *which* file g++ can't find, I'm suspecting that
the profiling intermediate files are removed in the first multilib
pass cleanup phase and not re-generated in the second and later
multilib passes.

Since I don't really understand the bprob tests, I tried checking to
see why the g77 and gcc bprob tests work with multilibs and the g++
ones don't.  The only real difference I can see between on one hand
g77.dg/bprob/bprob.exp & gcc.misc-tests/bprob.exp versus
g++.dg/bprob/bprob.exp is that the working languages have this extra
line:

 > set perf_ext tim

Since checking by running multilibs tests takes so long, I was hoping
someone could comment on this and let me know if I'm on the right
track.

		Thanks,
		--Kaveh

--
Kaveh R. Ghazi			ghazi@caip.rutgers.edu