[Bug fortran/58786] New: module function with passed character array of explicit length causes an ICE

[stefan.mauerberger at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58786

            Bug ID: 58786
           Summary: module function with passed character array of
                    explicit length causes an ICE
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: fortran
          Assignee: unassigned at gcc dot gnu.org
          Reporter: stefan.mauerberger at gmail dot com

Hello There! 

Assume a module function called "array_to_string()" whose return value is a
string. The length of the returned character is defined by the passed dummy
argument named "array" which is a character array of explicit length. 
The length of the returned character shall be determined by
SUM(LEN_TRIM(array)). Well, invoking the elemental function LEN_TRIM(array)
causes an internal compiler error. 

Please see the following example code. I know, it is tricky to explain:
> MODULE string_utilities_mod
>
> CONTAINS
>
>   FUNCTION array_to_string(array) RESULT(str)
>     CHARACTER(LEN=8) :: array(:)
>     ! CHARACTER(LEN=*) :: array(:) ! Does not cause an ICE
>     CHARACTER(LEN=SUM(LEN_TRIM(array))+1) :: str ! LEN_TRIM() is causing the ICE
>
>     WRITE(str,*) array(:) ! Imagine some fancy code
>
>   END FUNCTION array_to_string
>
> END MODULE string_utilities_mod
>
> PROGRAM test
>   USE string_utilities_mod
>
>   ! Just the invocation of array_to_string() causes an internal compiler error
>   PRINT *, array_to_string(['aaaaaaaa','bbbbbbbb'])
>
> CONTAINS
>
>   ! Everything works fine if array_to_string() is defined here
>
> END PROGRAM test

The above example has been tested with: 
 * Ifort 12.1 => ok
 * nagfor 5.3 => ok
 * pgfortran 13.8 => ok
However:
 * gfortran 4.4.5 => ICE
 * gfortran 4.7.2 => ICE
 * grfotran 4.8.1 => ICE
 * gfortran 4.9.  => ICE

Cheers, Stefan 

bug.f90: In function ‘test’:
bug.f90:20:0: internal compiler error: Segmentation fault
   PRINT *, array_to_string(['aaaaaaaa','bbbbbbbb'])
 ^
0x9ad52f crash_signal
        ../../gcc_trunk_src/gcc/toplev.c:335
0x7b3388 contains_struct_check
        ../../gcc_trunk_src/gcc/tree.h:2787
0x7b3388 size_binop_loc(unsigned int, tree_code, tree_node*, tree_node*)
        ../../gcc_trunk_src/gcc/fold-const.c:1492
0x81cff8 gimplify_compound_lval
        ../../gcc_trunk_src/gcc/gimplify.c:2214
0x815ff9 gimplify_expr(tree_node**, gimple_statement_d**, gimple_statement_d**,
bool (*)(tree_node*), int)
        ../../gcc_trunk_src/gcc/gimplify.c:7631
0x822e15 gimplify_addr_expr
        ../../gcc_trunk_src/gcc/gimplify.c:5073
0x8162be gimplify_expr(tree_node**, gimple_statement_d**, gimple_statement_d**,
bool (*)(tree_node*), int)
        ../../gcc_trunk_src/gcc/gimplify.c:7725
0x81ef49 gimplify_call_expr
        ../../gcc_trunk_src/gcc/gimplify.c:2645
0x815cb8 gimplify_expr(tree_node**, gimple_statement_d**, gimple_statement_d**,
bool (*)(tree_node*), int)
        ../../gcc_trunk_src/gcc/gimplify.c:7650
0x816a49 gimplify_expr(tree_node**, gimple_statement_d**, gimple_statement_d**,
bool (*)(tree_node*), int)
        ../../gcc_trunk_src/gcc/gimplify.c:8323
0x821f88 gimplify_modify_expr
        ../../gcc_trunk_src/gcc/gimplify.c:4772
0x815e64 gimplify_expr(tree_node**, gimple_statement_d**, gimple_statement_d**,
bool (*)(tree_node*), int)
        ../../gcc_trunk_src/gcc/gimplify.c:7679
0x81a196 gimplify_stmt(tree_node**, gimple_statement_d**)
        ../../gcc_trunk_src/gcc/gimplify.c:5613
0x81703b gimplify_statement_list
        ../../gcc_trunk_src/gcc/gimplify.c:1535
0x81703b gimplify_expr(tree_node**, gimple_statement_d**, gimple_statement_d**,
bool (*)(tree_node*), int)
        ../../gcc_trunk_src/gcc/gimplify.c:8068
0x81a196 gimplify_stmt(tree_node**, gimple_statement_d**)
        ../../gcc_trunk_src/gcc/gimplify.c:5613
0x817f7a gimplify_and_add
        ../../gcc_trunk_src/gcc/gimplify.c:339
0x817f7a gimplify_loop_expr
        ../../gcc_trunk_src/gcc/gimplify.c:1509
0x817f7a gimplify_expr(tree_node**, gimple_statement_d**, gimple_statement_d**,
bool (*)(tree_node*), int)
        ../../gcc_trunk_src/gcc/gimplify.c:7854
0x81a196 gimplify_stmt(tree_node**, gimple_statement_d**)
        ../../gcc_trunk_src/gcc/gimplify.c:5613