[Bug middle-end/50561] New: [4.7 regression] ICE when compiling zlib with -O2 -floop-flatten -floop-strip-mine

[matt at use dot net]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50561

             Bug #: 50561
           Summary: [4.7 regression] ICE when compiling zlib with -O2
                    -floop-flatten -floop-strip-mine
    Classification: Unclassified
           Product: gcc
           Version: 4.7.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: middle-end
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: matt@use.net


getting this with trunk r179143, on Ubuntu 11.10/x86-64:

/usr/lib/gcc-snapshot/bin/x86_64-linux-gnu-gcc  -O2 -floop-flatten
-floop-strip-mine -c ~/src/trees.i trees.c: In function 'init_block':
trees.c:414:13: internal compiler error: in psct_dynamic_dim, at
graphite-poly.h:659

It doesn't happen with -O1, or if you remove either of the loop options. This
doesn't happen with 4.6.1.

Pre-processed source is attached, but it quick to reproduce with zlib 1.2.3.4
sources.