Dear Fortranners,
we missed certain intrinsics as being disallowed in constant expressions,
which lead to an ICE when these intrinsics were used in a specification
expression with an initializer. The intrinsics in question are listed in
F2018:10.1.2.
As discussed in the PR, Steve recommended to omit TRANSFER from that list,
as it is special and might need separate treatment. I also could not come
up with a case where TRANSFER should not have simplified to a constant and
we would run into an issue. (We could leave that job to Gerhard... ;-).
However, in testing I encountered a case involving TRANSFER that is not
properly simplified, which seems orthogonal to the present case. I would
like to handle this separately. This case is mentioned in the testcase,
but commented out.
Regtested on x86_64-pc-linux-gnu. OK for mainline?
Thanks,
Harald
Fortran - improve checking for intrinsics allowed in constant expressions
gcc/fortran/ChangeLog:
PR fortran/102458
* expr.c (is_non_constant_intrinsic): Check for intrinsics
excluded in constant expressions (F2018:10.1.2).
(gfc_is_constant_expr): Use that check.
gcc/testsuite/ChangeLog:
PR fortran/102458
* gfortran.dg/pr102458.f90: New test.
diff --git a/gcc/fortran/expr.c b/gcc/fortran/expr.c
index 604e63e6164..5ad1c4f9523 100644
--- a/gcc/fortran/expr.c
+++ b/gcc/fortran/expr.c
@@ -990,6 +990,34 @@ done:
}
+/* Standard intrinsics listed under F2018:10.1.2 (6), which are excluded in
+ constant expressions, except TRANSFER (c.f. item (8)), which would need
+ separate treatment. */
+
+static bool
+is_non_constant_intrinsic (gfc_expr *e)
+{
+ if (e->expr_type == EXPR_FUNCTION
+ && e->value.function.isym)
+ {
+ switch (e->value.function.isym->id)
+ {
+ case GFC_ISYM_COMMAND_ARGUMENT_COUNT:
+ case GFC_ISYM_GET_TEAM:
+ case GFC_ISYM_NULL:
+ case GFC_ISYM_NUM_IMAGES:
+ case GFC_ISYM_TEAM_NUMBER:
+ case GFC_ISYM_THIS_IMAGE:
+ return true;
+
+ default:
+ return false;
+ }
+ }
+ return false;
+}
+
+
/* Determine if an expression is constant in the sense of F08:7.1.12.
* This function expects that the expression has already been simplified. */
@@ -1023,6 +1051,10 @@ gfc_is_constant_expr (gfc_expr *e)
gcc_assert (e->symtree || e->value.function.esym
|| e->value.function.isym);
+ /* Check for intrinsics excluded in constant expressions. */
+ if (e->value.function.isym && is_non_constant_intrinsic (e))
+ return false;
+
/* Call to intrinsic with at least one argument. */
if (e->value.function.isym && e->value.function.actual)
{
diff --git a/gcc/testsuite/gfortran.dg/pr102458.f90 b/gcc/testsuite/gfortran.dg/pr102458.f90
new file mode 100644
index 00000000000..555e4978fdb
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/pr102458.f90
@@ -0,0 +1,42 @@
+! { dg-do compile }
+! { dg-options "-fcoarray=lib" }
+! PR fortran/102458 - standard intrinsics excluded in constant expressions
+
+subroutine s1
+ integer :: a(command_argument_count()) = 1 ! { dg-error "Automatic array" }
+ print *, a
+end
+
+program p
+ block
+ integer :: a(get_team()) = 1 ! { dg-error "Automatic array" }
+ print *, a
+ end block
+end
+
+subroutine s2
+ integer :: a(num_images()) = 1 ! { dg-error "Automatic array" }
+ print *, a
+end
+
+function f()
+ block
+ integer :: a(team_number()) = 0 ! { dg-error "Automatic array" }
+ a = 1
+ end block
+end
+
+subroutine s3
+ integer :: a(this_image()) = 1 ! { dg-error "Automatic array" }
+ print *, a
+end
+
+subroutine s4
+ integer, parameter :: n = 4
+ integer, parameter :: x(transfer(n, n)) = 1 ! legal
+ integer :: y(transfer(n, n)) = 2 ! legal
+ integer, parameter :: k = size (x) ! ok
+! integer, parameter :: m = size (y) ! fails, tracked separately
+ print *, k, x, y
+ if (k /= size (y)) stop 1
+end
