[Bug c/70747] New: ICE on valid code on x86_64-linux-gnu: verify_gimple failed

[su at cs dot ucdavis.edu]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70747

            Bug ID: 70747
           Summary: ICE on valid code on x86_64-linux-gnu: verify_gimple
                    failed
           Product: gcc
           Version: 6.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
          Assignee: unassigned at gcc dot gnu.org
          Reporter: su at cs dot ucdavis.edu
  Target Milestone: ---

The following code causes an ICE when compiled with the current gcc trunk on
x86_64-linux-gnu in both 32-bit and 64-bit modes.  

It is a regression from 5.3.x. 


$ gcc-trunk -v
Using built-in specs.
COLLECT_GCC=gcc-trunk
COLLECT_LTO_WRAPPER=/usr/local/gcc-trunk/libexec/gcc/x86_64-pc-linux-gnu/7.0.0/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with: ../gcc-source-trunk/configure --enable-languages=c,c++,lto
--prefix=/usr/local/gcc-trunk --disable-bootstrap
Thread model: posix
gcc version 7.0.0 20160420 (experimental) [trunk revision 235250] (GCC) 
$ 
$ gcc-5.3 -c -w small.c
$ 
$ gcc-trunk -c -w small.c
small.c: In function ‘fn1’:
small.c:3:6: error: non-trivial conversion at assignment
 void fn1 ()
      ^~~
int
_Bool
b = 0;
small.c:3:6: internal compiler error: verify_gimple failed
0xba21fd verify_gimple_in_seq(gimple*)
        ../../gcc-source-trunk/gcc/tree-cfg.c:4792
0x8fb77b gimplify_body(tree_node*, bool)
        ../../gcc-source-trunk/gcc/gimplify.c:11501
0x8fbb36 gimplify_function_tree(tree_node*)
        ../../gcc-source-trunk/gcc/gimplify.c:11589
0x77a867 cgraph_node::analyze()
        ../../gcc-source-trunk/gcc/cgraphunit.c:625
0x77d3d0 analyze_functions
        ../../gcc-source-trunk/gcc/cgraphunit.c:1086
0x77e638 symbol_table::finalize_compilation_unit()
        ../../gcc-source-trunk/gcc/cgraphunit.c:2542
Please submit a full bug report,
with preprocessed source if appropriate.
Please include the complete backtrace with any bug report.
See <http://gcc.gnu.org/bugs.html> for instructions.
$ 


------------------------------------------


int *a, b;

void fn1 ()
{
  a = __builtin_malloc (sizeof(int)*2); 
  b = &a[1] == (0, 0);
}