[PATCH] Fortran: fix DATA and derived types with pointer components [PR114474]

[Harald Anlauf <anlauf@gmx.de>]

[-- Attachment #1: Type: text/plain, Size: 757 bytes --]

Dear all,

the attached patch fixes a 10+ regression for cases where a
derived type with a pointer component is used in a DATA statement.
The failure looked obscure, see testcase comments, and pointed
to a possible issue in the resolution (order).  For the failing
test, the target variable was seen with ts.type == BT_PROCEDURE
instead of its actual type.  For this reason, I restricted the
fixup as much as possible.

For details, please see the commit message.

Testcase cross-checked with NAG.

Regtested on x86_64-pc-linux-gnu.  OK for mainline?

If this fix survives broader testing, I would like to backport.

Thanks,
Harald

P.S.: while trying to extend coverage of conforming code, I had
much fun also with other compilers (e.g. NAG panicking...)


[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #2: pr114474.diff --]
[-- Type: text/x-patch, Size: 4619 bytes --]

From d5fda38243a22e1aef4367653d92521e53f2000d Mon Sep 17 00:00:00 2001
From: Harald Anlauf <anlauf@gmx.de>
Date: Wed, 27 Mar 2024 21:18:04 +0100
Subject: [PATCH] Fortran: fix DATA and derived types with pointer components
 [PR114474]

When matching actual arguments in match_actual_arg, these are initially
treated as a possible dummy procedure, assuming that the correct type is
determined later.  This resolution could fail when the procedure is a
derived type constructor with a pointer component and appears in a DATA
statement, where the pointer shall be associated with an initial data
target.  Check for those cases where the type obviously has not been
resolved yet, and which were missed because there was no component
reference.

gcc/fortran/ChangeLog:

	PR fortran/114474
	* primary.cc (gfc_variable_attr): Catch variables used in structure
	constructors within DATA statements that are still tagged with a
	temporary type BT_PROCEDURE from match_actual_arg and which have the
	target attribute, and fix their typespec.

gcc/testsuite/ChangeLog:

	PR fortran/114474
	* gfortran.dg/data_pointer_3.f90: New test.
---
 gcc/fortran/primary.cc                       | 12 +++
 gcc/testsuite/gfortran.dg/data_pointer_3.f90 | 77 ++++++++++++++++++++
 2 files changed, 89 insertions(+)
 create mode 100644 gcc/testsuite/gfortran.dg/data_pointer_3.f90

diff --git a/gcc/fortran/primary.cc b/gcc/fortran/primary.cc
index 0ab69bb9dce..5dd6875a4a6 100644
--- a/gcc/fortran/primary.cc
+++ b/gcc/fortran/primary.cc
@@ -2804,6 +2804,18 @@ gfc_variable_attr (gfc_expr *expr, gfc_typespec *ts)
   if (ts != NULL && expr->ts.type == BT_UNKNOWN)
     *ts = sym->ts;

+  /* Catch left-overs from match_actual_arg, where an actual argument of a
+     procedure is given a temporary ts.type == BT_PROCEDURE.  The fixup is
+     needed for structure constructors in DATA statements, where a pointer
+     is associated with a data target, and the argument has not been fully
+     resolved yet.  Components references are dealt with further below.  */
+  if (ts != NULL
+      && expr->ts.type == BT_PROCEDURE
+      && expr->ref == NULL
+      && attr.flavor != FL_PROCEDURE
+      && attr.target)
+    *ts = sym->ts;
+
   has_inquiry_part = false;
   for (ref = expr->ref; ref; ref = ref->next)
     if (ref->type == REF_INQUIRY)
diff --git a/gcc/testsuite/gfortran.dg/data_pointer_3.f90 b/gcc/testsuite/gfortran.dg/data_pointer_3.f90
new file mode 100644
index 00000000000..f0325cd5bcb
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/data_pointer_3.f90
@@ -0,0 +1,77 @@
+! { dg-do compile }
+! PR fortran/114474 - DATA and derived types with pointer components
+
+program pr114474
+  implicit none
+  integer, target     :: ii = 42    ! initial data target
+
+  integer, target     :: jj = 24
+  integer, pointer    :: qq => jj
+  ! ii and jj resolve slightly differently when the data statement below
+  ! is reached, as jj is resolved outside the structure constructor first
+
+  type t
+     integer, pointer :: h
+  end type t
+
+  integer, target     :: kk(7) =  23
+  integer, pointer    :: ll(:) => kk
+
+  type t1
+     integer          :: m(7)
+  end type t1
+
+  type(t)             :: x1, x2, x3, x4, x5
+  type(t), parameter  :: z1 = t(null())
+
+  type(t1), target    :: tt = t1([1,2,3,4,5,6,7])
+  type(t1), parameter :: vv = t1(22)
+  type(t1)            :: w1, w2
+  integer,  pointer   :: p1(:) => tt% m
+
+  data x1 / t(null())  /
+  data x2 / t(ii)      / ! ii is initial data target
+  data x3 / t(jj)      / ! jj is resolved differently...
+  data x4 / t(tt%m(3)) / ! pointer association with 3rd element
+
+  data w1 / t1(12)     /
+  data w2 / t1(vv%m)   /
+
+  if (      associated (x1% h)) stop 1
+  if (.not. associated (x2% h)) stop 2
+  if (.not. associated (x3% h)) stop 3
+  if (.not. associated (x4% h)) stop 4
+  if (x2% h /= 42) stop 5
+  if (x3% h /= 24) stop 6
+  if (x4% h /=  3) stop 7
+
+ if (any (w1%m /= 12  )) stop 8
+  if (any (w2%m /= vv%m)) stop 9
+end
+
+
+subroutine sub
+  implicit none
+
+  interface
+     real function myfun (x)
+       real, intent(in) :: x
+     end function myfun
+  end interface
+
+  type u
+     procedure(myfun), pointer, nopass :: p
+  end type u
+
+  type(u)            :: u3 = u(null())
+  type(u), parameter :: u4 = u(null())
+  type(u)            :: u1, u2
+
+  data u1 / u(null()) /
+  data u2 / u(myfun)  /
+end
+
+real function myfun (x)
+  real, intent(in) :: x
+  myfun = x
+end function myfun
--
2.35.3