| Summary: | [TR 15581 / F2003] Automatic reallocation on assignment to allocatable variables | ||
|---|---|---|---|
| Product: | gcc | Reporter: | Tobias Burnus <burnus> |
| Component: | fortran | Assignee: | Not yet assigned to anyone <unassigned> |
| Status: | RESOLVED FIXED | ||
| Severity: | normal | CC: | gcc-bugs, janus, kargls, t.r.hopkins, tkoenig |
| Priority: | P3 | Keywords: | wrong-code |
| Version: | 4.3.0 | ||
| Target Milestone: | --- | ||
| Host: | Target: | ||
| Build: | Known to work: | ||
| Known to fail: | Last reconfirmed: | 2008-11-10 19:46:00 | |
| Bug Depends on: | |||
| Bug Blocks: | 20585, 43366 | ||
|
Description
Tobias Burnus
2008-04-03 08:54:28 UTC
One thing to add: Seemingly gfortran supports reallocation for allocatable components (by itself a F2003 feature) using the constructor (see example), but not without constructor. Additionally, while a simple example (as below) works, the long example in the thread above is failing in some cases. (See link.) type t integer, allocatable :: a(:) end type t type(t) :: a allocate(a%a(1)) print *, size(a%a) ! print 1 (OK) a = t([1,2,3]) print *, size(a%a) ! prints 2 (OK) end Segfault with return values of allocatable functions. A code which does not work is the following TR15581-conform program. It seqfaults (SIGABRT) and valgrind shows errors of the kind: ==12853== Invalid write of size 4 ==12853== at 0x400966: MAIN__ (aa.f90:7) ==12853== Address 0x58e7b4c is 0 bytes after a block of size 4 alloc'd ==12853== at 0x4C256AE: malloc (in /usr/lib64/valgrind/amd64-linux/vgpreload_memcheck.so) ==12853== by 0x4008A4: MAIN__ (aa.f90:4) Test case: implicit none integer,allocatable :: j(:) integer :: i allocate(j(1)) do i = 1,200000 ! deallocate(j) j = alloc() end do contains function alloc() integer, allocatable :: alloc(:) allocate(alloc(10000)) end function end Additional test cases, probably related, to be re-checked: PR 36463, comment 12 PR 35971, comment 0 See also: http://groups.google.com/group/comp.lang.fortran/browse_thread/thread/fc7bdedfa4afc785 and note that the realloc shall not always happen: If <var> has TARGET attribute and the size is the same, no pointer to <var> may break. *** Bug 41003 has been marked as a duplicate of this bug. *** Note in Fortran 2008 (cf. PR 41719), polymorphic-variable = expr is allowed iff the variable is allocatable. Note: For coarrays/coindexed variables, the shape must be the same. That means that there is _no_ reallocate on assignment, cf. F2008, "7.2.1.2 Intrinsic assignment statement": "In an intrinsic assignment statement, [...] (3) the variable and expr shall be conformable unless the variable is an allocatable array that has the same rank as expr and is neither a coarray nor a coindexed object," Another test case, which requires PR45170 (allocable string lengths); it should print "|cdef|" (found at c.l.f in the thread "Problem with automatic reallocation of allocatable scalar on assignment") program tst character(len=:), allocatable :: S S='abcdef' S=S(3:) write(*,'("|",A,"|")')S end program tst Paul's draft patch: http://gcc.gnu.org/ml/fortran/2010-10/msg00100.html (In reply to comment #6) > Note in Fortran 2008 (cf. PR 41719), > polymorphic-variable = expr > is allowed iff the variable is allocatable. And note further that this is nontrivial as it requires a deep copy, cf. PR 46174. * * * Newer draft patch for realloc on assignment (w/o the polymorphic assignment): http://gcc.gnu.org/ml/fortran/2010-10/msg00213.html Author: pault Date: Sun Nov 28 13:47:26 2010 New Revision: 167220 URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=167220 Log: 2010-11-28 Paul Thomas <pault@gcc.gnu.org> PR fortran/35810 * trans-array.c (gfc_trans_array_constructor): If the loop->to is a VAR_DECL, assume this is dynamic. In this case, use the counter to obtain the value and set loop->to appropriately. (gfc_conv_ss_descriptor): Always save the offset of a variable in info.saved_offset. (gfc_conv_ss_startstride): Do not attempt bound checking of the lhs of an assignment, if allocatable and f2003 is allowed. (gfc_conv_loop_setup): If possible, do not use an allocatable lhs variable for the loopspec. (gfc_is_reallocatable_lhs): New function. (get_std_lbound): New function. (gfc_alloc_allocatable_for_assignment): New function. * gfortran.h : Add flag_realloc_lhs to the options structure. * lang.opt : Add option f(no-)realloc-lhs. * invoke.texi : Document option f(no-)realloc-lhs. * options.c (gfc_init_options, gfc_post_options, gfc_handle_option): Incorporate f(no-)realloc-lhs with default to frealloc_lhs for -std > f95. * trans-array.h : Add primitive for previous. * trans-expr.c (gfc_conv_string_length): Return if character length is a variable and the expression is NULL. (gfc_conv_procedure_call): If the call is of the kind x = f(...) and the lhs is allocatable and reallocation on assignment OK, call gfc_alloc_allocatable_for_assignment. Do not generate the function call unless direct by reference. (realloc_lhs_loop_for_fcn_call): New function. (realloc_lhs_bounds_for_intrinsic_call): New function. (gfc_trans_arrayfunc_assign): Reallocation assignments need a loopinfo and for the loop bounds to be set. With intrinsic functions, free the lhs data and let the library allocate the data array. Done by the new functions above. (gfc_trans_assignment_1): If the lhs is allocatable and reallocation on assignment is allowed, mark the lhs and use gfc_alloc_allocatable_for_assignment to make the reallocation. * trans.h : Add is_alloc_lhs bitfield to gfc_ss structure. 2010-11-28 Paul Thomas <pault@gcc.gnu.org PR fortran/35810 * gfortran.dg/realloc_on_assign_1.f03: New test. * gfortran.dg/realloc_on_assign_2.f03: New test. * gfortran.dg/transpose_2.f90: dg-option -fno-realloc-lhs. * gfortran.dg/unpack_bounds_1.f90: The same. * gfortran.dg/cshift_bounds_2.f90: The same. * gfortran.dg/matmul_bounds_2.f90: The same. * gfortran.dg/matmul_bounds_3.f90: The same. * gfortran.dg/matmul_bounds_4.f90: The same. * gfortran.dg/matmul_bounds_5.f90: The same. Added: trunk/gcc/testsuite/gfortran.dg/realloc_on_assign_1.f03 trunk/gcc/testsuite/gfortran.dg/realloc_on_assign_2.f03 Modified: trunk/gcc/fortran/ChangeLog trunk/gcc/fortran/gfortran.h trunk/gcc/fortran/invoke.texi trunk/gcc/fortran/lang.opt trunk/gcc/fortran/options.c trunk/gcc/fortran/trans-array.c trunk/gcc/fortran/trans-array.h trunk/gcc/fortran/trans-expr.c trunk/gcc/fortran/trans-types.c trunk/gcc/fortran/trans.h trunk/gcc/testsuite/ChangeLog trunk/gcc/testsuite/gfortran.dg/cshift_bounds_2.f90 trunk/gcc/testsuite/gfortran.dg/matmul_bounds_2.f90 trunk/gcc/testsuite/gfortran.dg/matmul_bounds_3.f90 trunk/gcc/testsuite/gfortran.dg/matmul_bounds_4.f90 trunk/gcc/testsuite/gfortran.dg/matmul_bounds_5.f90 trunk/gcc/testsuite/gfortran.dg/transpose_2.f90 trunk/gcc/testsuite/gfortran.dg/unpack_bounds_1.f90 Note: realloc_on_assign_2.f03 fails on current trunk when building with --disable-bootstrap (system compiler: gcc version 4.5.0 20100604 [gcc-4_5-branch revision 160292]):
realloc_on_assign_2.f03: In function ‘test5’:
realloc_on_assign_2.f03:101:0: internal compiler error: in fold_convert_loc, at fold-const.c:1906
Reduced test case:
program test5
real, allocatable, dimension (:,:) :: xwrkt
xwrkt = trs2a2 ()
contains
function trs2a2 ()
real, dimension (1:2,1:2) :: trs2a2
trs2a2 = 0.0
end function
end
Submitted patch for (re)allocate on intrinsic assignment -- now for scalars: http://gcc.gnu.org/ml/fortran/2011-01/msg00264.html Also supports (for scalars only) deferred-length character strings. Author: pault Date: Fri Jan 28 13:53:19 2011 New Revision: 169356 URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=169356 Log: 2011-01-28 Paul Thomas <pault@gcc.gnu.org> Tobias Burnus <burnus@gcc.gnu.org> PR fortran/45170 PR fortran/35810 PR fortran/47350 * interface.c (compare_actual_formal): An allocatable or pointer deferred length actual is only allowed if the formal argument is also deferred length. Clean up whitespace. * trans-expr.c (gfc_conv_procedure_call): Pass string length for deferred character length formal arguments by reference. Do the same for function results. (gfc_trans_pointer_assignment): Do not do runtime check of lhs and rhs character lengths, if deferred length lhs. In this case set the lhs character length to that of the rhs. (gfc_conv_string_parameter): Remove assert that string length is an integer type. (is_scalar_reallocatable_lhs): New function. (alloc_scalar_allocatable_for_assignment): New function. (gfc_trans_assignment_1): Call above new function. If the rhs is a deferred character length itself, makes ure that the function is called before reallocation, so that the length is available. (gfc_trans_asssignment): Remove error about assignment to deferred length character variables. * gfortran.texi : Update entry about (re)allocation on assignment. * trans-stmt.c (gfc_trans_allocate): Add code to handle deferred length character variables. * module.c (mio_typespec): Transfer deferred characteristic. * trans-types.c (gfc_get_function_type): New code to generate hidden typelist, so that those character lengths that are passed by reference get the right type. * resolve.c (resolve_contained_fntype): Supress error for deferred character length functions. (resolve_function, resolve_fl_procedure) The same. (check_symbols): Remove the error that support for entity with deferred type parameter is not yet implemented. (resolve_fl_derived): The same. match.c (alloc_opt_list): Allow MOLD for deferred length object. * trans-decl.c (gfc_get_symbol_decl): For deferred character length dummies, generate a local variable for string length. (create_function_arglist): Hidden length can be a pointer. (gfc_trans_deferred_vars): For deferred character length results and dummies, assign the string length to the local variable from the hidden argument on entry and the other way round on exit, as appropriate. 2011-01-28 Paul Thomas <pault@gcc.gnu.org> Tobias Burnus <burnus@gcc.gnu.org> PR fortran/45170 PR fortran/35810 PR fortran/47350 * gfortran.dg/realloc_on_assign_3.f03: New test. * gfortran.dg/realloc_on_assign_4.f03: New test. * gfortran.dg/realloc_on_assign_5.f90: New test. * gfortran.dg/allocatable_function_5.f90: New test. * gfortran.dg/allocate_deferred_char_scalar_1.f90: New test. * gfortran.dg/deferred_type_param_2.f90: Remove two "not yet implemented" dg-errors. Added: trunk/gcc/testsuite/gfortran.dg/allocate_deferred_char_scalar_1.f03 trunk/gcc/testsuite/gfortran.dg/realloc_on_assign_3.f03 trunk/gcc/testsuite/gfortran.dg/realloc_on_assign_4.f03 Modified: trunk/gcc/fortran/ChangeLog trunk/gcc/fortran/gfortran.texi trunk/gcc/fortran/interface.c trunk/gcc/fortran/match.c trunk/gcc/fortran/module.c trunk/gcc/fortran/resolve.c trunk/gcc/fortran/trans-decl.c trunk/gcc/fortran/trans-expr.c trunk/gcc/fortran/trans-stmt.c trunk/gcc/fortran/trans-types.c trunk/gcc/testsuite/ChangeLog trunk/gcc/testsuite/gfortran.dg/deferred_type_param_2.f90 Close as FIXED (for the 4.6 trunk). Left overs: - ICE mentioned in comment 12 - now PR 47516 - Assignment to polymorphic LHS, PR 43366 really mark as FIXED. Author: pault Date: Sun Jan 30 17:50:01 2011 New Revision: 169413 URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=169413 Log: 2011-01-30 Paul Thomas <pault@gcc.gnu.org> PR fortran/47523 * trans-expr.c (gfc_trans_assignment_1): If the rhs is an op expr and is assigned to a deferred character length scalar, make sure that the function is called before reallocation, so that the length is available. Include procedure pointer and procedure pointer component rhs as well. 2011-01-30 Paul Thomas <pault@gcc.gnu.org> PR fortran/47523 * trans-expr.c (gfc_trans_assignment_1): If the rhs is an op expr and is assigned to a deferred character length scalar, make sure that the function is called before reallocation, so that the length is available. Include procedure pointer and procedure pointer component rhs as well. PR fortran/45170 PR fortran/35810 PR fortran/47350 * gfortran.dg/allocatable_function_5.f90: New test not added by mistake on 2011-01-28. Added: trunk/gcc/testsuite/gfortran.dg/allocatable_function_5.f90 trunk/gcc/testsuite/gfortran.dg/realloc_on_assign_5.f03 Modified: trunk/gcc/fortran/ChangeLog trunk/gcc/fortran/trans-expr.c trunk/gcc/testsuite/ChangeLog Author: dnovillo Date: Wed Feb 2 17:59:29 2011 New Revision: 169666 URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=169666 Log: 2011-01-28 Paul Thomas <pault@gcc.gnu.org> Tobias Burnus <burnus@gcc.gnu.org> PR fortran/45170 PR fortran/35810 PR fortran/47350 * interface.c (compare_actual_formal): An allocatable or pointer deferred length actual is only allowed if the formal argument is also deferred length. Clean up whitespace. * trans-expr.c (gfc_conv_procedure_call): Pass string length for deferred character length formal arguments by reference. Do the same for function results. (gfc_trans_pointer_assignment): Do not do runtime check of lhs and rhs character lengths, if deferred length lhs. In this case set the lhs character length to that of the rhs. (gfc_conv_string_parameter): Remove assert that string length is an integer type. (is_scalar_reallocatable_lhs): New function. (alloc_scalar_allocatable_for_assignment): New function. (gfc_trans_assignment_1): Call above new function. If the rhs is a deferred character length itself, makes ure that the function is called before reallocation, so that the length is available. (gfc_trans_asssignment): Remove error about assignment to deferred length character variables. * gfortran.texi : Update entry about (re)allocation on assignment. * trans-stmt.c (gfc_trans_allocate): Add code to handle deferred length character variables. * module.c (mio_typespec): Transfer deferred characteristic. * trans-types.c (gfc_get_function_type): New code to generate hidden typelist, so that those character lengths that are passed by reference get the right type. * resolve.c (resolve_contained_fntype): Supress error for deferred character length functions. (resolve_function, resolve_fl_procedure) The same. (check_symbols): Remove the error that support for entity with deferred type parameter is not yet implemented. (resolve_fl_derived): The same. match.c (alloc_opt_list): Allow MOLD for deferred length object. * trans-decl.c (gfc_get_symbol_decl): For deferred character length dummies, generate a local variable for string length. (create_function_arglist): Hidden length can be a pointer. (gfc_trans_deferred_vars): For deferred character length results and dummies, assign the string length to the local variable from the hidden argument on entry and the other way round on exit, as appropriate. 2011-01-28 Paul Thomas <pault@gcc.gnu.org> Tobias Burnus <burnus@gcc.gnu.org> PR fortran/45170 PR fortran/35810 PR fortran/47350 * gfortran.dg/realloc_on_assign_3.f03: New test. * gfortran.dg/realloc_on_assign_4.f03: New test. * gfortran.dg/realloc_on_assign_5.f90: New test. * gfortran.dg/allocatable_function_5.f90: New test. * gfortran.dg/allocate_deferred_char_scalar_1.f90: New test. * gfortran.dg/deferred_type_param_2.f90: Remove two "not yet implemented" dg-errors. Added: branches/google/integration/gcc/testsuite/gfortran.dg/allocate_deferred_char_scalar_1.f03 branches/google/integration/gcc/testsuite/gfortran.dg/realloc_on_assign_3.f03 branches/google/integration/gcc/testsuite/gfortran.dg/realloc_on_assign_4.f03 Modified: branches/google/integration/gcc/fortran/ChangeLog branches/google/integration/gcc/fortran/gfortran.texi branches/google/integration/gcc/fortran/interface.c branches/google/integration/gcc/fortran/match.c branches/google/integration/gcc/fortran/module.c branches/google/integration/gcc/fortran/resolve.c branches/google/integration/gcc/fortran/trans-decl.c branches/google/integration/gcc/fortran/trans-expr.c branches/google/integration/gcc/fortran/trans-stmt.c branches/google/integration/gcc/fortran/trans-types.c branches/google/integration/gcc/testsuite/ChangeLog branches/google/integration/gcc/testsuite/gfortran.dg/deferred_type_param_2.f90 Author: dnovillo Date: Wed Feb 2 18:04:21 2011 New Revision: 169697 URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=169697 Log: 2011-01-30 Paul Thomas <pault@gcc.gnu.org> PR fortran/47523 * trans-expr.c (gfc_trans_assignment_1): If the rhs is an op expr and is assigned to a deferred character length scalar, make sure that the function is called before reallocation, so that the length is available. Include procedure pointer and procedure pointer component rhs as well. 2011-01-30 Paul Thomas <pault@gcc.gnu.org> PR fortran/47523 * trans-expr.c (gfc_trans_assignment_1): If the rhs is an op expr and is assigned to a deferred character length scalar, make sure that the function is called before reallocation, so that the length is available. Include procedure pointer and procedure pointer component rhs as well. PR fortran/45170 PR fortran/35810 PR fortran/47350 * gfortran.dg/allocatable_function_5.f90: New test not added by mistake on 2011-01-28. Added: branches/google/integration/gcc/testsuite/gfortran.dg/allocatable_function_5.f90 branches/google/integration/gcc/testsuite/gfortran.dg/realloc_on_assign_5.f03 Modified: branches/google/integration/gcc/fortran/ChangeLog branches/google/integration/gcc/fortran/trans-expr.c branches/google/integration/gcc/testsuite/ChangeLog |