[Bug analyzer/103032] false positive diagnostic from -fanalyzer about double-free

[dmalcolm at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103032

--- Comment #1 from David Malcolm <dmalcolm at gcc dot gnu.org> ---
I haven't yet reproduced the precise symptoms you reported, but FWIW I'm seeing
this in got_gsd, which looks like a true warning for this code:

           | 1903 |             psects[psectid] = strdup(name);
           |      |                               ~~~~~~~~~~~~
           |      |                               |
           |      |                               (43) this call could return
NULL
           | 1904 |             trim(psects[psectid++]);
           |      |             ~~~~~~~~~~~~~~~~~~~~~~~
           |      |             |
           |      |             (44) calling ‘trim’ from ‘got_gsd’
           |
           +--> ‘trim’: events 45-46
                  |
                  | 1800 | void trim(
                  |      |      ^~~~
                  |      |      |
                  |      |      (45) entry to ‘trim’
                  |......
                  | 1805 |     for (cp = buf + strlen(buf); cp > buf; cp--)
                  |      |                     ~~~~~~~~~~~
                  |      |                     |
                  |      |                     (46) argument 1 (‘buf’) from
(43) could be NULL where non-null expected
                  |
../../src/gcc/testsuite/gcc.dg/analyzer/pr103032.c:1173:8: note: argument 1 of
‘strlen’ must be non-null
 1173 | size_t strlen(const char *);
      |        ^~~~~~