When I compile the attached C++ test case with mainline with the options -O3 -W, I get the warning:
/home/ian/foo1.cc:29: warning: ‘sv$a$1’ is used uninitialized in this function I think it is trying to give me the useful warning that sv.a[1] is uninitialized, which it is. However, using the bogus name sv$a$1 is more confusing than useful. I get no warning from gcc 3.4.2 -- Summary: [4.0 Regression] Confusing warning about uninitialized variable Product: gcc Version: 4.0.0 Status: UNCONFIRMED Severity: minor Priority: P3 Component: tree-optimization AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: ian at airs dot com CC: gcc-bugs at gcc dot gnu dot org GCC build triplet: i686-pc-linux-gnu GCC host triplet: i686-pc-linux-gnu GCC target triplet: i686-pc-linux-gnu http://gcc.gnu.org/bugzilla/show_bug.cgi?id=19651