[gcc r12-7032] Fortran: reject simplifying TRANSFER for MOLD with storage size 0

[Harald Anlauf <anlauf@gcc.gnu.org>]

https://gcc.gnu.org/g:4e4252db0348a7274663a892c3a96d3ed7702aff

commit r12-7032-g4e4252db0348a7274663a892c3a96d3ed7702aff
Author: Harald Anlauf <anlauf@gmx.de>
Date:   Tue Feb 1 23:33:24 2022 +0100

    Fortran: reject simplifying TRANSFER for MOLD with storage size 0
    
    gcc/fortran/ChangeLog:
    
            PR fortran/104311
            * check.cc (gfc_calculate_transfer_sizes): Checks for case when
            storage size of SOURCE is greater than zero while the storage size
            of MOLD is zero and MOLD is an array shall not depend on SIZE.
    
    gcc/testsuite/ChangeLog:
    
            PR fortran/104311
            * gfortran.dg/transfer_simplify_15.f90: New test.

Diff:
---
 gcc/fortran/check.cc                               |  2 +-
 gcc/testsuite/gfortran.dg/transfer_simplify_15.f90 | 11 +++++++++++
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/gcc/fortran/check.cc b/gcc/fortran/check.cc
index d6c6767ae9e..fc97bb1371e 100644
--- a/gcc/fortran/check.cc
+++ b/gcc/fortran/check.cc
@@ -6150,7 +6150,7 @@ gfc_calculate_transfer_sizes (gfc_expr *source, gfc_expr *mold, gfc_expr *size,
    * representation is not shorter than that of SOURCE.
    * If SIZE is present, the result is an array of rank one and size SIZE.
    */
-  if (result_elt_size == 0 && *source_size > 0 && !size
+  if (result_elt_size == 0 && *source_size > 0
       && (mold->expr_type == EXPR_ARRAY || mold->rank))
     {
       gfc_error ("%<MOLD%> argument of %<TRANSFER%> intrinsic at %L is an "
diff --git a/gcc/testsuite/gfortran.dg/transfer_simplify_15.f90 b/gcc/testsuite/gfortran.dg/transfer_simplify_15.f90
new file mode 100644
index 00000000000..cdbec97ae71
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/transfer_simplify_15.f90
@@ -0,0 +1,11 @@
+! { dg-do compile }
+! PR fortran/104311 - ICE out of memory
+! Contributed by G.Steinmetz
+
+program p
+  type t
+  end type
+  type(t) :: x(2)
+  print *, transfer(1,x,2)       ! { dg-error "shall not have storage size 0" }
+  print *, transfer(1,x,huge(1)) ! { dg-error "shall not have storage size 0" }
+end