The following valid testcase triggers an ICE on mainline when compiled with "-fmudflap -O":
================================= struct A { int i, j; }; int foo(long long int x) { return ((struct A*)&x)->j; } ================================= bug.c: In function 'foo': bug.c:7: internal compiler error: in mf_xform_derefs_1, at tree-mudflap.c:789 Please submit a full bug report, [etc.] The regression was introduced between 2008-05-03 and 2008-05-13. -- Summary: [4.4 regression] ICE with pointer cast and -fmudflap Product: gcc Version: 4.4.0 Status: UNCONFIRMED Keywords: ice-on-valid-code, monitored Severity: normal Priority: P3 Component: libmudflap AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: reichelt at gcc dot gnu dot org http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36397