strange test failures

[Jeff Law]

On 12/08/2016 04:47 PM, Martin Sebor wrote:
> I'm seeing failures in a few C tests that I'm not sure what to make
> out of.  The tests fail due to undefined symbols while linking even
> though they're not meant to link.  Among these are a number (but not
> all) of the gcc.dg/divmod-[1-6]{-simode}.c tests.
>
>   FAIL: gcc.dg/divmod-1.c (test for excess errors)
>
> The log shows that they are being built without the -S option:
>
> spawn -ignore SIGHUP /opt/notnfs/msebor/build/gcc-78622/gcc/xgcc
> -B/opt/notnfs/msebor/build/gcc-78622/gcc/
> /opt/notnfs/msebor/src/gcc/gcc-78622/gcc/testsuite/gcc.dg/divmod-1.c
> -fno-diagnostics-show-caret -fdiagnostics-color=never -O2
> -fdump-tree-widening_mul-details -lm -o ./divmod-1.exe
> /lib/../lib64/crt1.o: In function `_start':
> (.text+0x20): undefined reference to `main'
> ...
>
> When I run make check-c I get these same failures in different tests.
>
> In successful builds the logs show that the tests are only assembled
> (i.e., compiled with -S), never linked.
>
> I can reproduce this on two different x86_64 machines but so far
> only with my patches to GCC (the middle end but none of these tests
> or the GCC .exp files).  Is it possible that somehow my changes cause
> this?  (The removal of the -S option.)  Am I missing something about
> how GCC tests are run?
IIRC the default for a dg test is to compile, but not assemble or run. 
The log shows that it's trying to go through the link step.



>
> Thanks
> Martin
>
> PS I also see other strange errors like
>
> RROR: tcl error sourcing
> /opt/notnfs/msebor/src/gcc/gcc-78622/gcc/testsuite/gcc.c-torture/execute/execute.exp.
>
> ERROR: unmatched open brace in list
>
> ERROR: tcl error sourcing
> /opt/notnfs/msebor/src/gcc/gcc-78622/gcc/testsuite/gcc.c-torture/execute/ieee/ieee.exp.
>
> ERROR: torture-init: torture_without_loops is not empty as expected
This all sounds like you've got a mucked up testsuite/lib directory or 
something like that.  I'd start by verifying the contents of your 
testsuite/lib directory.

I did a testrun on Dec 7 on the trunk and didn't see any of these problems.

jeff