[PATCH] PR fortran/43996 -- Too large array constructor in SPREAD

[Steve Kargl]

The attached patch fixes an issue with SPREAD and the PARAMETER
attribute when an array constructor is too large for expansion.
gfortran now issues an error message and points to the 
-fmax-array-constructor.

Patch built on i386-*-freebsd and x86_64-*-freebsd.  There are
no regressions.  OK to commit?

2015-11-17  Steven G. Kargl  

PR fortran/43996
* simplify.c (gfc_simplify_spread): Issue error for too large array 
constructor in a PARAMETER statement.

2015-11-17  Steven G. Kargl  

PR fortran/43996
* gfortran.dg/pr43996.f90

-- 
Steve
Index: gcc/fortran/simplify.c
===
--- gcc/fortran/simplify.c	(revision 230463)
+++ gcc/fortran/simplify.c	(working copy)
@@ -5991,8 +5991,8 @@ gfc_simplify_spacing (gfc_expr *x)
 gfc_expr *
 gfc_simplify_spread (gfc_expr *source, gfc_expr *dim_expr, gfc_expr *ncopies_expr)
 {
-  gfc_expr *result = 0L;
-  int i, j, dim, ncopies;
+  gfc_expr *result = NULL;
+  int nelem, i, j, dim, ncopies;
   mpz_t size;
 
   if ((!gfc_is_constant_expr (source)
@@ -6019,8 +6019,20 @@ gfc_simplify_spread (gfc_expr *source, g
   else
 mpz_init_set_ui (size, 1);
 
-  if (mpz_get_si (size)*ncopies > flag_max_array_constructor)
-return NULL;
+  nelem = mpz_get_si (size) * ncopies;
+  if (nelem > flag_max_array_constructor)
+{
+  if (gfc_current_ns->sym_root->n.sym->attr.flavor == FL_PARAMETER)
+	{
+	  gfc_error ("The number of elements (%d) in the array constructor "
+		 "at %L requires an increase of the allowed %d upper "
+		 "limit.  See %<-fmax-array-constructor%> option.",
+		 nelem, >where, flag_max_array_constructor);
+	  return _bad_expr;
+	}
+  else
+	return NULL;
+}
 
   if (source->expr_type == EXPR_CONSTANT)
 {
Index: gcc/testsuite/gfortran.dg/pr43996.f90
===
--- gcc/testsuite/gfortran.dg/pr43996.f90	(nonexistent)
+++ gcc/testsuite/gfortran.dg/pr43996.f90	(working copy)
@@ -0,0 +1,7 @@
+! { dg-do compile }
+! PR fortran/43996
+!
+real, parameter :: a(720,360) = spread((/(j, j=1,720) /), dim=2, ncopies=360) ! { dg-error "number of elements" }
+real x
+x = a(720,360)
+end

Re: [PATCH] PR fortran/43996 -- Too large array constructor in SPREAD

[Jerry DeLisle]

On 11/17/2015 08:05 AM, Steve Kargl wrote:
> The attached patch fixes an issue with SPREAD and the PARAMETER
> attribute when an array constructor is too large for expansion.
> gfortran now issues an error message and points to the 
> -fmax-array-constructor.
> 
> Patch built on i386-*-freebsd and x86_64-*-freebsd.  There are
> no regressions.  OK to commit?
> 
OK