[Bug bootstrap/64197] New: [5 regression] SPARC bootstrap broken: SEGV in tree_estimate_loop_size

["ro at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64197

            Bug ID: 64197
           Summary: [5 regression] SPARC bootstrap broken: SEGV in
                    tree_estimate_loop_size
           Product: gcc
           Version: 5.0
            Status: UNCONFIRMED
          Severity: critical
          Priority: P3
         Component: bootstrap
          Assignee: unassigned at gcc dot gnu.org
          Reporter: ro at gcc dot gnu.org
                CC: ebotcazou at gcc dot gnu.org
              Host: sparc*-sun-solaris2.*
            Target: sparc*-sun-solaris2.*
             Build: sparc*-sun-solaris2.*

Between 20141128 (r218141) and 20141205 (r218417) SPARC bootstrap got broken
compiling the 64-bit stage2 libcc1. The following testcase is extracted from
building _ffsdi2.o, but the same happens for many other files:

cc1 -fpreprocessed libgcc2.i -mptr64 -mcpu=v9 -quiet -m64 -O2 -o libgcc2.s
/vol/gcc/src/hg/trunk/local/libgcc/libgcc2.c: In function '__ffsti2':
/vol/gcc/src/hg/trunk/local/libgcc/libgcc2.c:528:1: internal compiler error:
Bus Error
 __ffsDI2 (DWtype u)
 ^

Running cc1 under gdb finds

Program received signal SIGSEGV, Segmentation fault.
[Switching to Thread 1 (LWP 1)]
0x00903928 in tree_estimate_loop_size(loop*, edge_def*, edge_def*, loop_size*,
int) ()
(gdb) where
#0  0x00903928 in tree_estimate_loop_size(loop*, edge_def*, edge_def*,
loop_size*, int) ()
#1  0x00904c60 in canonicalize_loop_induction_variables(loop*, bool,
unroll_level, bool) ()
#2  0x00906388 in tree_unroll_loops_completely_1(bool, bool, vec<loop*,
va_heap, vl_ptr>&, loop*) ()
#3  0x009062f4 in tree_unroll_loops_completely_1(bool, bool, vec<loop*,
va_heap, vl_ptr>&, loop*) ()
#4  0x0090663c in tree_unroll_loops_completely(bool, bool) ()
#5  0x00906c5c in (anonymous
namespace)::pass_complete_unrolli::execute(function*) ()
#6  0x006ddd0c in execute_one_pass(opt_pass*) ()
#7  0x006de1f4 in execute_pass_list_1(opt_pass*) [clone .constprop.71] ()
#8  0x006de218 in execute_pass_list_1(opt_pass*) [clone .constprop.71] ()
#9  0x006de25c in execute_pass_list(function*, opt_pass*) ()
#10 0x0039a6fc in cgraph_node::expand() ()
#11 0x0039c388 in symbol_table::compile() ()
#12 0x0039e1c0 in symbol_table::finalize_compilation_unit() ()
#13 0x00226a60 in c_write_global_declarations() ()
#14 0x007b045c in compile_file() ()
#15 0x00e99620 in toplev::main(int, char**) ()
#16 0x00e9a044 in main ()

  Rainer