[Patch, fortran] PR87127 - External function not recognised from within an associate block
Hi All,
I committed this to 8-branch on 2019-04-24 but not to 9-branch. I have no
record of why I did this.
The patch now requires an additional line,
&& sym->ns->proc_name->attr.proc != PROC_MODULE
to prevent the error message in pr88376.f90 from changing to the less
helpful
Error: Specification function ‘n’ at (1) must be PURE
I propose to commit to mainline and backport to 12-branch unless there are
objections in the next 24 hours.
Cheers
Paul
Fortran: Recognise external function from within an associate block
that has not been declared as external [PR87127]
2023-03-19 Paul Thomas
gcc/fortran
PR fortran/87127
* resolve.cc (check_host_association): If an external function
is typed but not declared explicitly to be external, change the
old symbol from a variable to an external function.
gcc/testsuite/
PR fortran/87127
* gfortran.dg/external_procedures_4.f90: New test.
diff --git a/gcc/fortran/resolve.cc b/gcc/fortran/resolve.cc
index ba603b4c407..a947f908ece 100644
--- a/gcc/fortran/resolve.cc
+++ b/gcc/fortran/resolve.cc
@@ -6079,11 +6079,14 @@ resolve_procedure:
/* Checks to see that the correct symbol has been host associated.
- The only situation where this arises is that in which a twice
- contained function is parsed after the host association is made.
- Therefore, on detecting this, change the symbol in the expression
- and convert the array reference into an actual arglist if the old
- symbol is a variable. */
+ The only situations where this arises are:
+ (i) That in which a twice contained function is parsed after
+ the host association is made. On detecting this, change
+ the symbol in the expression and convert the array reference
+ into an actual arglist if the old symbol is a variable; or
+ (ii) That in which an external function is typed but not declared
+ explcitly to be external. Here, the old symbol is changed
+ from a variable to an external function. */
static bool
check_host_association (gfc_expr *e)
{
@@ -6185,6 +6188,27 @@ check_host_association (gfc_expr *e)
gfc_resolve_expr (e);
sym->refs++;
}
+ /* This case corresponds to a call, from a block or a contained
+ procedure, to an external function, which has not been declared
+ as being external in the main program but has been typed. */
+ else if (sym && old_sym != sym
+ && !e->ref
+ && sym->ts.type == BT_UNKNOWN
+ && old_sym->ts.type != BT_UNKNOWN
+ && sym->attr.flavor == FL_PROCEDURE
+ && old_sym->attr.flavor == FL_VARIABLE
+ && sym->ns->parent == old_sym->ns
+ && sym->ns->proc_name
+ && sym->ns->proc_name->attr.proc != PROC_MODULE
+ && (sym->ns->proc_name->attr.flavor == FL_LABEL
+ || sym->ns->proc_name->attr.flavor == FL_PROCEDURE))
+ {
+ old_sym->attr.flavor = FL_PROCEDURE;
+ old_sym->attr.external = 1;
+ old_sym->attr.function = 1;
+ old_sym->result = old_sym;
+ gfc_resolve_expr (e);
+ }
}
/* This might have changed! */
return e->expr_type == EXPR_FUNCTION;
! { dg-do run }
!
! Test the fix for PR87127 in which the references to exfunc cause
! the error "exfunc at (1) is not a function".
!
! Contributed by Gerhard Steinmetz
!
function exfunc(i)
implicit none
integer :: exfunc,i
exfunc = 2*i
end function
! contents of test.f90
program test
implicit none
integer :: exfunc,i
integer,parameter :: array(2)=[6,7]
associate(i=>array(2))! Original bug
if (exfunc(i) .ne. 2*i) stop 1
end associate
i = 99
call foo
contains
subroutine foo() ! Comment #3
if (exfunc(i) .ne. 2*i) stop 2
end subroutine foo
end program
Re: [Patch, fortran] PR87127 - External function not recognised from within an associate block
Hi Dominique, I discovered the same thing myself this morning. The patch was developed on 8-branch because my working trunk had a hefty patch in an intermediate state of development. I cleared it off,ready to do the commit, and discovered the change on regtesting. I am trying to think of a way in which to distinguish the two cases. Thanks Paul On Sun, 31 Mar 2019 at 10:33, Dominique d'Humières wrote: > > Hi Paul, > > With your patch the error for the test gfortran.dg/pr88376.f90 is changed from > > Error: 'n' at (1) is not a function > > to > > Error: Specification function 'n' at (1) must be PURE > > TIA > > Dominique -- "If you can't explain it simply, you don't understand it well enough" - Albert Einstein
Re: [Patch, fortran] PR87127 - External function not recognised from within an associate block
Hi Paul, With your patch the error for the test gfortran.dg/pr88376.f90 is changed from Error: 'n' at (1) is not a function to Error: Specification function 'n' at (1) must be PURE TIA Dominique
Re: [Patch, fortran] PR87127 - External function not recognised from within an associate block
Hi Paul, Bootstrapped and regtested on FC29/x86_64 - OK for trunk? OK - looks obvious enough, and, IMO, is quite unlikely to cause a regressions. Thanks for the patch! Regards Thomas
[Patch, fortran] PR87127 - External function not recognised from within an associate block
This patch is pretty self-explanatory. I have checked that a sensible
errors are given if 'exfunc' in the testcase is referenced if it is a
variable.
Bootstrapped and regtested on FC29/x86_64 - OK for trunk?
Paul
2019-03-30 Paul Thomas
PR fortran/87127
* resolve.c (check_host_association): If an external function
is typed but not declared explicitly to be external, change the
old symbol from a variable to an external function.
2019-03-30 Paul Thomas
PR fortran/87127
* gfortran.dg/external_procedures_4.f90: New test.
Index: gcc/fortran/resolve.c
===
*** gcc/fortran/resolve.c (revision 269160)
--- gcc/fortran/resolve.c (working copy)
*** resolve_procedure:
*** 5615,5625
/* Checks to see that the correct symbol has been host associated.
!The only situation where this arises is that in which a twice
!contained function is parsed after the host association is made.
!Therefore, on detecting this, change the symbol in the expression
!and convert the array reference into an actual arglist if the old
!symbol is a variable. */
static bool
check_host_association (gfc_expr *e)
{
--- 5615,5628
/* Checks to see that the correct symbol has been host associated.
!The only situations where this arises are:
! (i) That in which a twice contained function is parsed after
! the host association is made. On detecting this, change
! the symbol in the expression and convert the array reference
! into an actual arglist if the old symbol is a variable; or
! (ii) That in which an external function is typed but not declared
! explicitly to be external. Here, the old symbol is changed
! from a variable to an external function. */
static bool
check_host_association (gfc_expr *e)
{
*** check_host_association (gfc_expr *e)
*** 5709,5714
--- 5712,5737
gfc_resolve_expr (e);
sym->refs++;
}
+ /* This case corresponds to a call, from a block or a contained
+ procedure, to an external function, which has not been declared
+ as being external in the main program but has been typed. */
+ else if (sym && old_sym != sym
+ && !e->ref
+ && sym->ts.type == BT_UNKNOWN
+ && old_sym->ts.type != BT_UNKNOWN
+ && sym->attr.flavor == FL_PROCEDURE
+ && old_sym->attr.flavor == FL_VARIABLE
+ && sym->ns->parent == old_sym->ns
+ && sym->ns->proc_name
+ && (sym->ns->proc_name->attr.flavor == FL_LABEL
+ || sym->ns->proc_name->attr.flavor == FL_PROCEDURE))
+ {
+ old_sym->attr.flavor = FL_PROCEDURE;
+ old_sym->attr.external = 1;
+ old_sym->attr.function = 1;
+ old_sym->result = old_sym;
+ gfc_resolve_expr (e);
+ }
}
/* This might have changed! */
return e->expr_type == EXPR_FUNCTION;
Index: gcc/testsuite/gfortran.dg/external_procedures_4.f90
===
*** gcc/testsuite/gfortran.dg/external_procedures_4.f90 (nonexistent)
--- gcc/testsuite/gfortran.dg/external_procedures_4.f90 (working copy)
***
*** 0
--- 1,28
+ ! { dg-do run }
+ !
+ ! Test the fix for PR87127 in which the references to exfunc cause
+ ! the error "‘exfunc’ at (1) is not a function".
+ !
+ ! Contributed by Gerhard Steinmetz
+ !
+ function exfunc(i)
+ implicit none
+ integer :: exfunc,i
+ exfunc = 2*i
+ end function
+
+ ! contents of test.f90
+ program test
+ implicit none
+ integer :: exfunc,i
+ integer,parameter :: array(2)=[6,7]
+ associate(i=>array(2))! Original bug
+ if (exfunc(i) .ne. 2*i) stop 1
+ end associate
+ i = 99
+ call foo
+ contains
+ subroutine foo() ! Comment #3
+ if (exfunc(i) .ne. 2*i) stop 2
+ end subroutine foo
+ end program
