[Bug fortran/67674] New: Incorrect result or ICE for deferred-length character component

[kristopher.kuhlman at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67674

            Bug ID: 67674
           Summary: Incorrect result or ICE for deferred-length character
                    component
           Product: gcc
           Version: 6.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: fortran
          Assignee: unassigned at gcc dot gnu.org
          Reporter: kristopher.kuhlman at gmail dot com
  Target Milestone: ---

Created attachment 36368
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=36368&action=edit
test program

The attached test case results in incorrect results from trunk version of
gfortran (6.0). The same program gives a "not yet supported" message from 4.8.4
and gives an internal compiler error for 4.9.3. Using Ubuntu 14.04. Intel
compiler (15.03) gives expected results.

Maybe related to bug 50221?

1) Expected results (Intel compiler)
-------------------------------------
 length main program before           0
 length intermediate before           0
 length inner before           0
 length inner after          28
 here the word is finally set
 length intermediate after          28
 here the word is finally set
 length main program after          28
 final result:here the word is finally set


2) Trunk gfortran output (compiled will -Wall -Wextra)
------------------------------------------------------
 length main program before           0
 length intermediate before           0
 length inner before           0
 length inner after          28
 here the word is finally set
 length intermediate after          28
 here the word is finally set
 length main program after           0
 final result:


3) Gfortran 4.9.3 output 
------------------------
test_allocatable_string.f90: In function ‘test’:
test_allocatable_string.f90:10:0: internal compiler error: in gimplify_expr, at
gimplify.c:8538
   allocate(character(len=0) :: my_string_type%name)
 ^
0x7c5472 gimplify_expr(tree_node**, gimple_statement_base**,
gimple_statement_base**, bool (*)(tree_node*), int)
        ../../gcc-4.9.3/gcc/gimplify.c:8538
0x7ca719 gimplify_modify_expr
        ../../gcc-4.9.3/gcc/gimplify.c:4510
0x7c3c31 gimplify_expr(tree_node**, gimple_statement_base**,
gimple_statement_base**, bool (*)(tree_node*), int)
        ../../gcc-4.9.3/gcc/gimplify.c:7627
0x7c66f6 gimplify_stmt(tree_node**, gimple_statement_base**)
        ../../gcc-4.9.3/gcc/gimplify.c:5373
0x7c4b0b gimplify_statement_list
        ../../gcc-4.9.3/gcc/gimplify.c:1432
0x7c4b0b gimplify_expr(tree_node**, gimple_statement_base**,
gimple_statement_base**, bool (*)(tree_node*), int)
        ../../gcc-4.9.3/gcc/gimplify.c:8042
0x7c66f6 gimplify_stmt(tree_node**, gimple_statement_base**)
        ../../gcc-4.9.3/gcc/gimplify.c:5373
0x7c3b5c gimplify_and_add
        ../../gcc-4.9.3/gcc/gimplify.c:385
0x7c3b5c gimplify_expr(tree_node**, gimple_statement_base**,
gimple_statement_base**, bool (*)(tree_node*), int)
        ../../gcc-4.9.3/gcc/gimplify.c:7964
0x7c66f6 gimplify_stmt(tree_node**, gimple_statement_base**)
        ../../gcc-4.9.3/gcc/gimplify.c:5373
0x7c6f96 gimplify_bind_expr
        ../../gcc-4.9.3/gcc/gimplify.c:1099
0x7c3a2a gimplify_expr(tree_node**, gimple_statement_base**,
gimple_statement_base**, bool (*)(tree_node*), int)
        ../../gcc-4.9.3/gcc/gimplify.c:7824
0x7c66f6 gimplify_stmt(tree_node**, gimple_statement_base**)
        ../../gcc-4.9.3/gcc/gimplify.c:5373
0x7c763a gimplify_body(tree_node*, bool)
        ../../gcc-4.9.3/gcc/gimplify.c:8734
0x7c7987 gimplify_function_tree(tree_node*)
        ../../gcc-4.9.3/gcc/gimplify.c:8887
0x6c4877 cgraph_analyze_function(cgraph_node*)
        ../../gcc-4.9.3/gcc/cgraphunit.c:648
0x6c56b7 analyze_functions
        ../../gcc-4.9.3/gcc/cgraphunit.c:1016
0x6c6415 finalize_compilation_unit()
        ../../gcc-4.9.3/gcc/cgraphunit.c:2328
0x82f844 write_global_declarations()
        ../../gcc-4.9.3/gcc/langhooks.c:323
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