Re: [PATCH] contrib: Make dg-extract-results.py tolerant of unparseable files

[Andrew Pinski <andrew.pinski@oss.qualcomm.com>]

On Thu, May 14, 2026 at 11:18 AM Kevin Buettner <kevinb@redhat.com> wrote:
>
> This commit is for the benefit of GDB, but as the binutils-gdb
> repository shares the contrib/ directory with GCC, this commit
> must first be applied to GCC and then copied back to binutils-gdb.
>
> When running GDB tests in parallel (make check -j$(nproc)), the
> consolidated gdb.sum and gdb.log files are produced by
> contrib/dg-extract-results.py, which merges per-test output files.
>
> If any single per-test output file is malformed (e.g., due to a
> DejaGnu EILSEQ crash, which is how I encountered this problem), the
> script aborts via self.fatal().  Because this script is invoked via a
> Makefile command using shell redirection, this causes the top-level
> output files to be left as empty, zero-byte files, discarding valid
> results from all other tests.
>
> Fix by making the script tolerant of unparseable input files.  Wrap
> each file's parsing in a try/except block.  When a file cannot be
> parsed, emit a warning to stderr and continue processing remaining
> files.  This ensures that crashing tests do not destroy the
> consolidated output for the entire parallel build.
>
> Tested on Fedora 44 using the GCC testsuite (make check-gcc
> -j$(nproc)). The consolidated results are produced correctly with
> no regressions.
>
> This commit fixes this GDB bug:
>
> https://sourceware.org/bugzilla/show_bug.cgi?id=34147
>
> contrib/ChangeLog:
>
>         * dg-extract-results.py: Show warnings instead of erroring out
>         when encountering an unparseable file.

Ok.

> ---
>  contrib/dg-extract-results.py | 44 +++++++++++++++++++++++++----------
>  1 file changed, 32 insertions(+), 12 deletions(-)
>
> diff --git a/contrib/dg-extract-results.py b/contrib/dg-extract-results.py
> index c7060753500..98b0f4989c9 100644
> --- a/contrib/dg-extract-results.py
> +++ b/contrib/dg-extract-results.py
> @@ -34,6 +34,16 @@ if sys.version_info >= (3, 0):
>      sys.stdout = io.TextIOWrapper (sys.stdout.buffer,
>                                     errors = 'surrogateescape')
>
> +# Exception raised to skip a file that cannot be parsed.  Used when
> +# a summary or log file is malformed (e.g. due to a DejaGnu EILSEQ
> +# crash).  We will warn about the file and continue processing the
> +# rest.
> +class ParseError (Exception):
> +    def __init__ (self, filename, message):
> +        Exception.__init__ (self, filename + ': ' + message)
> +        self.filename = filename
> +        self.message = message
> +
>  class Named:
>      def __init__ (self, name):
>          self.name = name
> @@ -205,7 +215,7 @@ class Prog:
>          try:
>              return int (value)
>          except ValueError:
> -            self.fatal (filename, 'expected an integer, got: ' + value)
> +            raise ParseError (filename, 'expected an integer, got: ' + value)
>
>      # Return a list that represents no test results.
>      def zero_counts (self):
> @@ -229,7 +239,7 @@ class Prog:
>          while True:
>              line = file.readline()
>              if line == '':
> -                self.fatal (filename, 'could not parse variation list')
> +                raise ParseError (filename, 'could not parse variation list')
>              if line == '\n':
>                  break
>              self.known_variations.add (line.strip())
> @@ -264,7 +274,7 @@ class Prog:
>          while True:
>              line = file.readline()
>              if line == '':
> -                self.fatal (filename, 'no recognised summary line')
> +                raise ParseError (filename, 'no recognised summary line')
>              if line == end:
>                  break
>
> @@ -292,7 +302,7 @@ class Prog:
>              match = self.result_re.match (line)
>              if match and (harness or not line.startswith ('WARNING:')):
>                  if not harness:
> -                    self.fatal (filename, 'saw test result before harness name')
> +                    raise ParseError (filename, 'saw test result before harness name')
>                  name = match.group (2)
>                  # Ugly hack to get the right order for gfortran.
>                  if name.startswith ('gfortran.dg/g77/'):
> @@ -354,7 +364,7 @@ class Prog:
>                      found = True
>                      break
>              if not found:
> -                self.fatal (filename, 'unknown test result: ' + line[:-1])
> +                raise ParseError (filename, 'unknown test result: ' + line[:-1])
>
>      # Parse an acats run, which uses a different format from dejagnu.
>      # We have just skipped over '=== acats configuration ==='.
> @@ -367,7 +377,7 @@ class Prog:
>          while True:
>              line = file.readline()
>              if line == '':
> -                self.fatal (filename, 'could not parse acats preamble')
> +                raise ParseError (filename, 'could not parse acats preamble')
>              if line == '\t\t=== acats tests ===\n':
>                  break
>              if record:
> @@ -423,9 +433,9 @@ class Prog:
>              if line.startswith ('Running target '):
>                  name = line[len ('Running target '):-1]
>                  if not tool:
> -                    self.fatal (filename, 'could not parse tool name')
> +                    raise ParseError (filename, 'could not parse tool name')
>                  if name not in self.known_variations:
> -                    self.fatal (filename, 'unknown target: ' + name)
> +                    raise ParseError (filename, 'unknown target: ' + name)
>                  self.parse_run (filename, file, tool,
>                                  tool.get_variation (name),
>                                  num_variations)
> @@ -474,7 +484,7 @@ class Prog:
>              # individual runs) and parse the version output.
>              if tool and line == '\t\t=== ' + tool.name + ' Summary ===\n':
>                  if file.readline() != '\n':
> -                    self.fatal (filename, 'expected blank line after summary')
> +                    raise ParseError (filename, 'expected blank line after summary')
>                  self.parse_final_summary (filename, file)
>                  continue
>
> @@ -490,7 +500,7 @@ class Prog:
>              # Sanity check to make sure that important text doesn't get
>              # dropped accidentally.
>              if strict and line.strip() != '':
> -                self.fatal (filename, 'unrecognised line: ' + line[:-1])
> +                raise ParseError (filename, 'unrecognised line: ' + line[:-1])
>
>      # Output a segment of text.
>      def output_segment (self, segment):
> @@ -569,8 +579,18 @@ class Prog:
>          try:
>              # Parse the input files.
>              for filename in self.files:
> -                with safe_open (filename) as file:
> -                    self.parse_file (filename, file)
> +                try:
> +                    with safe_open (filename) as file:
> +                        self.parse_file (filename, file)
> +                except ParseError as e:
> +                    # Partial state from this file is intentionally retained.
> +                    # This preserves any valid results and diagnostic ERROR
> +                    # lines that were parsed before the error, which is
> +                    # important for diagnosing problems like DejaGnu crashes.
> +                    # The unprocessed remainder of the file is lost.
> +                    sys.stderr.write ('warning: skipping ' + e.filename + ': '
> +                                      + e.message
> +                                      + '; results may be incomplete\n')
>
>              # Decide what to output.
>              if len (self.variations) == 0:
> --
> 2.54.0
>