[Bug c/36296] New: wrong warning about potential uninitialized variable

["zimmerma+gcc at loria dot fr" <gcc-bugzilla at gcc dot gnu dot org>]

When compiling mpfr-2.3.1 with gcc-4.3, one gets the following warning
(among others):
{{{
lngamma.c: In function 'mpfr_lngamma_aux':
lngamma.c:160: warning: 'B' may be used uninitialized in this function
}}}
However, looking at the code shows that this variable cannot be used
uninitialized:
* a variable Bm is initialized to zero
* if Bm=0, B is initialized using an auxiliary function, and Bm is set to 2
  (this code is in a do { ... } while loop, thus is always executed)


-- 
           Summary: wrong warning about potential uninitialized variable
           Product: gcc
           Version: 4.3.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: zimmerma+gcc at loria dot fr
 GCC build triplet: x86_64-unknown-linux-gnu
  GCC host triplet: x86_64-unknown-linux-gnu
GCC target triplet: x86_64-unknown-linux-gnu


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36296