After reading all other PRs about uninitialized variable warnings, I
believe this one is a different situtation.
PR 20968 -- is about inlining, which is not involved here
PR 21733 -- is about two concatenated blocks rather than nested ones
PR 31707 -- is about setjmp
PR 20644 -- is also about unreachable code
In this testcase, it is really obvious to the observer that the switch
statement explicitly handles all the cases where it could be reached
from the outer if statement, and thus always assigns a value to
variable areg. GCC 3.x did not warn about it.
I verified the warning is still generated with SVN revision 131533.
(The code is taken from a project called simulavr, and has been cut
down to the minimal test case reproducing the warning.)
--
Summary: [Regression 4.1/4.3] warning: 'areg' may be used
uninitialized in this function
Product: gcc
Version: 4.3.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: middle-end
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: j at uriah dot heep dot sax dot de
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34793
