Dear all,
the attached simple patch fixes an ICE for ALLOCATE with SOURCE=
of a deferred-length character array with source-expression
being an array of character with length zero. The reason was
that the array descriptor of the source-expression was discarded
in the special case of length 0.
Solution: restrict special case to rank 0.
Regtested on x86_64-pc-linux-gnu. OK for mainline?
The offending code was introduced during 7-development,
so it is technically a regression. I would therefore
like to backport after waiting for a week or two.
Thanks,
Harald
From ae5e3654d30d17584cfcfc3bbcc48cf75cb7453c Mon Sep 17 00:00:00 2001
From: Harald Anlauf
Date: Mon, 3 Jun 2024 22:02:06 +0200
Subject: [PATCH] Fortran: fix ALLOCATE with SOURCE=, zero-length character
[PR83865]
gcc/fortran/ChangeLog:
PR fortran/83865
* trans-stmt.cc (gfc_trans_allocate): Restrict special case for
source-expression with zero-length character to rank 0, so that
the array shape is not discarded.
gcc/testsuite/ChangeLog:
PR fortran/83865
* gfortran.dg/allocate_with_source_32.f90: New test.
---
gcc/fortran/trans-stmt.cc | 3 +-
.../gfortran.dg/allocate_with_source_32.f90 | 33 +++
2 files changed, 35 insertions(+), 1 deletion(-)
create mode 100644 gcc/testsuite/gfortran.dg/allocate_with_source_32.f90
diff --git a/gcc/fortran/trans-stmt.cc b/gcc/fortran/trans-stmt.cc
index 9b497d6bdc6..93b633e212e 100644
--- a/gcc/fortran/trans-stmt.cc
+++ b/gcc/fortran/trans-stmt.cc
@@ -6449,8 +6449,9 @@ gfc_trans_allocate (gfc_code * code, gfc_omp_namelist *omp_allocate)
else
gfc_add_block_to_block (, );
- /* Special case when string in expr3 is zero. */
+ /* Special case when string in expr3 is scalar and has length zero. */
if (code->expr3->ts.type == BT_CHARACTER
+ && code->expr3->rank == 0
&& integer_zerop (se.string_length))
{
gfc_init_se (, NULL);
diff --git a/gcc/testsuite/gfortran.dg/allocate_with_source_32.f90 b/gcc/testsuite/gfortran.dg/allocate_with_source_32.f90
new file mode 100644
index 000..4a9bd46da4d
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/allocate_with_source_32.f90
@@ -0,0 +1,33 @@
+! { dg-do run }
+!
+! PR fortran/83865
+!
+! Test ALLOCATE with SOURCE= of deferred length character, where
+! the source-expression is an array of character with length 0.
+
+program p
+ implicit none
+ character(:), allocatable :: z(:)
+ character(1) :: cc(4) = ""
+ allocate (z, source=[''])
+ if (len (z) /= 0 .or. size (z) /= 1) stop 1
+ deallocate (z)
+ allocate (z, source=['',''])
+ if (len (z) /= 0 .or. size (z) /= 2) stop 2
+ deallocate (z)
+ allocate (z, source=[ character(0) :: 'a','b','c'])
+ if (len (z) /= 0 .or. size (z) /= 3) stop 3
+ deallocate (z)
+ allocate (z, source=[ character(0) :: cc ])
+ if (len (z) /= 0 .or. size (z) /= 4) stop 4
+ deallocate (z)
+ associate (x => f())
+if (len (x) /= 0 .or. size (x) /= 1) stop 5
+if (x(1) /= '') stop 6
+ end associate
+contains
+ function f() result(z)
+character(:), allocatable :: z(:)
+allocate (z, source=[''])
+ end function f
+end
--
2.35.3
