------- Comment #6 from dave dot korn dot cygwin at gmail dot com 2009-05-30
16:12 -------
Groan.
PASS: gfortran.dg/Wall.f90 (test for excess errors)
spawn [open ...]
Internal Error: insert(): Duplicate key found!
FAIL: gfortran.dg/Wall.f90 execution test
In other words, exactly what Andrew warned would happen.
Breakpoint 1, __main () at /gnu/winsup/src/winsup/cygwin/dcrt0.cc:993
993 do_global_ctors (user_data->ctors, false);
(gdb) bt
#0 __main () at /gnu/winsup/src/winsup/cygwin/dcrt0.cc:993
#1 0x00401166 in main ()
(gdb) c
Continuing.
Breakpoint 1, __main () at /gnu/winsup/src/winsup/cygwin/dcrt0.cc:993
993 do_global_ctors (user_data->ctors, false);
(gdb) bt
#0 __main () at /gnu/winsup/src/winsup/cygwin/dcrt0.cc:993
#1 0x004010ee in MAIN__ ()
#2 0x00401191 in main ()
(gdb)
For some reason though, there isn't any call to __main in MAIN__ in my original
"hello world" testcase, only in main. I don't yet understand that. It may be
to do with the usage of main_program_symbol() in parse.c, which is called from
two places:
case ST_PROGRAM:
if (seen_program)
goto duplicate_main;
seen_program = 1;
prog_locus = gfc_current_locus;
push_state (&s, COMP_PROGRAM, gfc_new_block);
main_program_symbol(gfc_current_ns, gfc_new_block->name);
accept_statement (st);
/* Anything else starts a nameless main program block. */
default:
if (seen_program)
goto duplicate_main;
seen_program = 1;
prog_locus = gfc_current_locus;
push_state (&s, COMP_PROGRAM, gfc_new_block);
main_program_symbol (gfc_current_ns, "MAIN__");
I'm not sure yet what happens when we take the first one of these clauses and
create a main function that is not called "MAIN__", because there is code in
gfc_sym_mangled_function_id in trans-decl.c that assumes any main function has
the same name:
/* Main program is mangled into MAIN__. */
if (sym->attr.is_main_program)
return get_identifier ("MAIN__");
Possibly this is an inconsistency, and if there's a named main block we create
a main function but then look up what will effectively be an unrelated name. I
need advice from someone who knows the fortran compiler internals better than
me.
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40309
