[Bug c++/71628] New: ICE on valid C++11 code (with lambda expression, __typeof operator and variable length array): verify_gimple failed

[su at cs dot ucdavis.edu]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71628

            Bug ID: 71628
           Summary: ICE on valid C++11 code (with lambda expression,
                    __typeof operator and variable length array):
                    verify_gimple failed
           Product: gcc
           Version: 7.0
            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 C++11 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 also affects 4.8.x and later, and is a regression from 4.7.x. 


sica [159] % g++-4.7 -c small.cpp -std=c++11
sica [160] % sh
$ g++-trunk -v
Using built-in specs.
COLLECT_GCC=g++-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 20160622 (experimental) [trunk revision 237715] (GCC)
$
$ g++-4.7 -c -std=c++11 small.cpp
$ clang++ -c -std=c++11 small.cpp
$
$ g++-trunk -c -std=c++11 small.cpp
small.cpp: In lambda function:
small.cpp:6:5: error: Local declaration from a different function
   [&] { __typeof (a) x; } ();
     ^
D.2029
small.cpp:6:22: note: in statement
   [&] { __typeof (a) x; } ();
                      ^
_1 = (sizetype) D.2029;
small.cpp:6:5: error: Local declaration from a different function
   [&] { __typeof (a) x; } ();
     ^
D.2029
small.cpp:6:22: note: in statement
   [&] { __typeof (a) x; } ();
                      ^
_5 = (sizetype) D.2029;
small.cpp:6:5: internal compiler error: verify_gimple failed
   [&] { __typeof (a) x; } ();
     ^
0xdff39f verify_gimple_in_cfg(function*, bool)
        ../../gcc-source-trunk/gcc/tree-cfg.c:5212
0xce9212 execute_function_todo
        ../../gcc-source-trunk/gcc/passes.c:1964
0xce9c0b execute_todo
        ../../gcc-source-trunk/gcc/passes.c:2016
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 i;

void foo ()
{ 
  int a[i];
  [&] { __typeof (a) x; } ();
}