[Bug c/17246] New: Feature request: optional malloc type warning

["Gyro at zeta-soft dot com" <gcc-bugzilla at gcc dot gnu dot org>]

Hi,

It would be very nice to have an option to check the return type of `malloc'. 
Most calls to malloc fit this pattern:

  struct frob *P;
  P = malloc(sizeof(struct frob));
or
  P = malloc(N * sizeof(struct frob));

It's not too hard to accidentally write, for example

  P = malloc(N * sizeof(struct frob *));

It would be nice to have a `-Wmalloc-type' option, say, that would recognize
instances of the common patterns and check that the type being allocated matched
the type being assigned to.  (Whether it should be activated by `-Wall' is not
clear; it depends on the false positive rate, I suppose.)

For this to be completely useful, there will also have to be some way to specify
the name of the allocation routine (`malloc' by default).  One of the primary
uses I would have for it, for instance, would be on Linux kernel code, which
uses `kmalloc'.

It's possible I could be persuaded to tackle this myself, but since I haven't
hacked on GCC before it would be nice to have a clue where to start and what
approach to take... five minutes of your time could save me hours.

-- 
           Summary: Feature request: optional malloc type warning
           Product: gcc
           Version: 3.3.1
            Status: UNCONFIRMED
          Severity: enhancement
          Priority: P2
         Component: c
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: Gyro at zeta-soft dot com
                CC: gcc-bugs at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17246