Re: Segfault while processing groff manual

[Gavin Smith]

On Mon, Feb 13, 2023 at 09:32:56PM +0100, Patrice Dumas wrote:
> 
> May be fixed in
> https://git.savannah.gnu.org/cgit/texinfo.git/commit/?id=606f3c94201213524b0f1a776b559126dfc973c9
> 
> But not sure that it is exactly the same error as the one valgrind
> reports.

It doesn't segfault anymore but there is still an error.  I simplified
the test case to

\input texinfo

@deffn NNN

@bye

which is invalid input, but still shouldn't have valgrind errors.  In
the log file there is:

==309255== Invalid read of size 4
==309255==    at 0x6EB0093: relocate_source_marks (source_marks.c:215)
==309255==    by 0x6EADF19: split_def_args (def.c:284)
==309255==    by 0x6EADF19: parse_def (def.c:309)
==309255==    by 0x6EA4511: end_line_def_line (end_line.c:2121)
==309255==    by 0x6EA4D9F: end_line_starting_block (end_line.c:1027)
==309255==    by 0x6EA7257: end_line (end_line.c:2392)
==309255==    by 0x6E9CAB3: process_remaining_on_line (parser.c:2212)
==309255==    by 0x6E9DE9E: parse_texi (parser.c:2342)
==309255==    by 0x6E9688C: parse_file (api.c:210)
==309255==    by 0x6E94DB3: XS_Texinfo__Parser_parse_file (Parsetexi.c:222)
==309255==    by 0x2119D7: Perl_pp_entersub (in /usr/bin/perl)
==309255==    by 0x208135: Perl_runops_standard (in /usr/bin/perl)
==309255==    by 0x17B8DB: perl_run (in /usr/bin/perl)
==309255==  Address 0x4e08fe0 is 0 bytes after a block of size 0 alloc'd
==309255==    at 0x483DD99: calloc (in 
/usr/lib/x86_64-linux-gnu/valgrind/vgpreload_memcheck-amd64-linux.so)
==309255==    by 0x6EAFFF4: relocate_source_marks (source_marks.c:194)
==309255==    by 0x6EADF19: split_def_args (def.c:284)
==309255==    by 0x6EADF19: parse_def (def.c:309)
==309255==    by 0x6EA4511: end_line_def_line (end_line.c:2121)
==309255==    by 0x6EA4D9F: end_line_starting_block (end_line.c:1027)
==309255==    by 0x6EA7257: end_line (end_line.c:2392)
==309255==    by 0x6E9CAB3: process_remaining_on_line (parser.c:2212)
==309255==    by 0x6E9DE9E: parse_texi (parser.c:2342)
==309255==    by 0x6E9688C: parse_file (api.c:210)
==309255==    by 0x6E94DB3: XS_Texinfo__Parser_parse_file (Parsetexi.c:222)
==309255==    by 0x2119D7: Perl_pp_entersub (in /usr/bin/perl)
==309255==    by 0x208135: Perl_runops_standard (in /usr/bin/perl)
==309255== 
==309255== 
==309255== HEAP SUMMARY:
==309255==     in use at exit: 17,072,077 bytes in 61,701 blocks
==309255==   total heap usage: 200,510 allocs, 138,809 frees, 40,497,199 bytes 
allocated
==309255== 
==309255== LEAK SUMMARY:
==309255==    definitely lost: 37,016 bytes in 36 blocks
==309255==    indirectly lost: 61,240 bytes in 28 blocks
==309255==      possibly lost: 16,707,290 bytes in 61,365 blocks
==309255==    still reachable: 266,531 bytes in 272 blocks
==309255==                       of which reachable via heuristic:
==309255==                         newarray           : 151,240 bytes in 4,248 
blocks
==309255==         suppressed: 0 bytes in 0 blocks


Also, "a block of size 0" allocated looks unusual.