A combination of options can yield the error: internal compiler error: in remove_unreachable_handlers, at tree-eh.c
To produce the error, g++ is invoked thus: g++ -c -pipe --trapv --non-call-exceptions --stack-check -O2 Aside from -pipe and -O2, which can be further decomposed, the options are the minimal set to produce the error in this case. Build from URL: svn://gcc.gnu.org/svn/gcc/branches/gcc-4_5-branch Repository Root: svn://gcc.gnu.org/svn/gcc Repository UUID: 138bc75d-0d04-0410-961f-82ee72b054a4 Revision: 160774 unset LDFLAGS export CFLAGS=-pipe export CXXFLAGS=-pipe configure --enable-languages=c++ make bootstrap-lean See attachment for source code of test case. Taken from geany/scintilla. -- Summary: internal compiler error: in remove_unreachable_handlers, at tree-eh Product: gcc Version: 4.5.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: tree-optimization AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: gxgjyyozme at zrmshffbt dot mine dot nu http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44545