Random C testsuite failures for gcc-3_0-branch (i686-pc-linux-gnu)

[Andris Pavenis]

I'm getting some testsuite failures randomly appearing and disappearing when 
running GCC C testsuite (nightly bootstrapping and testing current CVS 
version of gcc-3.0 branch for i686-pc-linux-gnu). I rerun 'make check-gcc'
today and got different test results with same sources and binaries.

Andris

Source:   gcc 3.0 branch (last updated 2002 Jan 07  01:01  +0200)
System:   Linux kernel 2.4.17
          glibc-2.2.3
          binutils-2.11.90.0.31
          Pentium III, 512Mb RAM	

		=== gcc tests ===


Running target unix
XPASS: gcc.c-torture/execute/20000801-4.c execution,  -O0 
XPASS: gcc.c-torture/execute/20000801-4.c execution,  -O1 
XPASS: gcc.c-torture/execute/20000801-4.c execution,  -O2 
XPASS: gcc.c-torture/execute/20000801-4.c execution,  -O3 -fomit-frame-pointer 
XPASS: gcc.c-torture/execute/20000801-4.c execution,  -O3 -g 
XPASS: gcc.c-torture/execute/20000801-4.c execution,  -Os 
FAIL: gcc.dg/format/c99-scanf-1.c %hhu sign (test for warnings, line 144)

		=== gcc Summary ===

# of expected passes		15342
# of unexpected failures	1
# of unexpected successes	6
# of expected failures		77
# of unsupported tests		20
/disk2/cvs/gcc30/build/build.lnx/gcc/xgcc version 3.0.4 20020106 (prerelease)

Later I rerun GCC tests once more and no more got failure for gcc/dg/format/c99-scanf-1.c.
Other results of  C tests where identical. I'm including diffs of log files of both runs of C testsuite 
in attachment

For example day before I got even more failures, but only source changes were in date in versions: