[PATCH 0/4] Avoid command-line length limit combining test results

On Windows, "make check-parallel" dies when combining the per-test
gdb.sum / gdb.log files into the final combined pair:

 $ find outputs/ -name gdb.sum | wc -l
 2657
 .../dg-extract-results.sh: line 39: /ucrt64/bin/python3: Argument list too long
 make: *** [Makefile:274: check-parallel] Error 2

The testsuite Makefile passes the whole file list to
contrib/dg-extract-results.sh on the command line, expanded from a
find(1) backtick.  GDB's parallel harness writes one gdb.sum (and one
gdb.log) per test script, so on a full run that list holds thousands
of paths, which overflows the Windows command-line length limit
(~32 KB).

This series teaches dg-extract-results to read the file list from
stdin (or a file) instead, and has the Makefile pipe the find output
straight in, so the length limit no longer applies regardless of the
host.

The first patch touches contrib/dg-extract-results.{sh,py}, which are
shared with GCC, so I plan to submit that one to GCC as well.

The two middle patches (factoring out the combine recipe, and adding
the extract-results target) are pure GDB and can go in at any time.

Only the last patch depends on the new -f option added by the first
patch.

Pedro Alves (4):
  dg-extract-results.{sh,py}: Optionally read file list from stdin/file
  gdb/testsuite: Factor out dg-extract-results.sh calls
  gdb/testsuite: Add extract-results make target
  gdb/testsuite: Pipe the dg-extract-results file list via stdin

 contrib/dg-extract-results.py | 30 +++++++++++++++++++---
 contrib/dg-extract-results.sh | 17 +++++++++++--
 gdb/testsuite/Makefile.in     | 47 ++++++++++++++++++++++++-----------
 3 files changed, 74 insertions(+), 20 deletions(-)


base-commit: 39fc0cc4aa6f82a73b9eac6b8739895484ab269f
-- 
2.54.0