libgfortran: Don't skip allocation if size is zero [PR112412]

In the function template of transformational functions doing a reduction
of an array along one dimension, if the passed in result array was
unallocated and the calculated allocation size was zero (this is the case
of empty result arrays), an early return used to skip the allocation.  This
change moves the allocation before the early return, so that empty result
arrays are not seen as unallocated.  This is possible because zero size is
explicitly supported by the allocation function.

The offending code is present in several places, and this updates them all.
More precisely, there is one place in the template for logical reductions,
and there are two places in the templates corresponding to masked reductions
with respectively array mask and scalar mask.  Templates for unmasked
reductions, which already allocate before returning, are not affected, but
unmasked reductions are checked nevertheless in the testcase.  The affected
m4 files are ifunction.m4 for regular functions and types, ifunction-s.m4
for character minloc and maxloc, ifunction-s2.m4 for character minval and
maxval, and ifunction_logical for logical reductions.

	PR fortran/112412

libgfortran/ChangeLog:

	* m4/ifunction.m4 (START_MASKED_ARRAY_FUNCTION, SCALAR_ARRAY_FUNCTION):
	Don't skip allocation if the allocation size is zero.
	* m4/ifunction-s.m4 (START_MASKED_ARRAY_FUNCTION,
	SCALAR_ARRAY_FUNCTION): Ditto.
	* m4/ifunction-s2.m4 (START_MASKED_ARRAY_FUNCTION,
	SCALAR_ARRAY_FUNCTION): Ditto.
	* m4/ifunction_logical.m4 (START_ARRAY_FUNCTION): Ditto.
	* generated/all_l1.c: Regenerate.
	* generated/all_l16.c: Regenerate.
	* generated/all_l2.c: Regenerate.
	* generated/all_l4.c: Regenerate.
	* generated/all_l8.c: Regenerate.
	* generated/any_l1.c: Regenerate.
	* generated/any_l16.c: Regenerate.
	* generated/any_l2.c: Regenerate.
	* generated/any_l4.c: Regenerate.
	* generated/any_l8.c: Regenerate.
	* generated/count_16_l.c: Regenerate.
	* generated/count_1_l.c: Regenerate.
	* generated/count_2_l.c: Regenerate.
	* generated/count_4_l.c: Regenerate.
	* generated/count_8_l.c: Regenerate.
	* generated/iall_i1.c: Regenerate.
	* generated/iall_i16.c: Regenerate.
	* generated/iall_i2.c: Regenerate.
	* generated/iall_i4.c: Regenerate.
	* generated/iall_i8.c: Regenerate.
	* generated/iany_i1.c: Regenerate.
	* generated/iany_i16.c: Regenerate.
	* generated/iany_i2.c: Regenerate.
	* generated/iany_i4.c: Regenerate.
	* generated/iany_i8.c: Regenerate.
	* generated/iparity_i1.c: Regenerate.
	* generated/iparity_i16.c: Regenerate.
	* generated/iparity_i2.c: Regenerate.
	* generated/iparity_i4.c: Regenerate.
	* generated/iparity_i8.c: Regenerate.
	* generated/maxloc1_16_i1.c: Regenerate.
	* generated/maxloc1_16_i16.c: Regenerate.
	* generated/maxloc1_16_i2.c: Regenerate.
	* generated/maxloc1_16_i4.c: Regenerate.
	* generated/maxloc1_16_i8.c: Regenerate.
	* generated/maxloc1_16_r10.c: Regenerate.
	* generated/maxloc1_16_r16.c: Regenerate.
	* generated/maxloc1_16_r17.c: Regenerate.
	* generated/maxloc1_16_r4.c: Regenerate.
	* generated/maxloc1_16_r8.c: Regenerate.
	* generated/maxloc1_16_s1.c: Regenerate.
	* generated/maxloc1_16_s4.c: Regenerate.
	* generated/maxloc1_4_i1.c: Regenerate.
	* generated/maxloc1_4_i16.c: Regenerate.
	* generated/maxloc1_4_i2.c: Regenerate.
	* generated/maxloc1_4_i4.c: Regenerate.
	* generated/maxloc1_4_i8.c: Regenerate.
	* generated/maxloc1_4_r10.c: Regenerate.
	* generated/maxloc1_4_r16.c: Regenerate.
	* generated/maxloc1_4_r17.c: Regenerate.
	* generated/maxloc1_4_r4.c: Regenerate.
	* generated/maxloc1_4_r8.c: Regenerate.
	* generated/maxloc1_4_s1.c: Regenerate.
	* generated/maxloc1_4_s4.c: Regenerate.
	* generated/maxloc1_8_i1.c: Regenerate.
	* generated/maxloc1_8_i16.c: Regenerate.
	* generated/maxloc1_8_i2.c: Regenerate.
	* generated/maxloc1_8_i4.c: Regenerate.
	* generated/maxloc1_8_i8.c: Regenerate.
	* generated/maxloc1_8_r10.c: Regenerate.
	* generated/maxloc1_8_r16.c: Regenerate.
	* generated/maxloc1_8_r17.c: Regenerate.
	* generated/maxloc1_8_r4.c: Regenerate.
	* generated/maxloc1_8_r8.c: Regenerate.
	* generated/maxloc1_8_s1.c: Regenerate.
	* generated/maxloc1_8_s4.c: Regenerate.
	* generated/maxval1_s1.c: Regenerate.
	* generated/maxval1_s4.c: Regenerate.
	* generated/maxval_i1.c: Regenerate.
	* generated/maxval_i16.c: Regenerate.
	* generated/maxval_i2.c: Regenerate.
	* generated/maxval_i4.c: Regenerate.
	* generated/maxval_i8.c: Regenerate.
	* generated/maxval_r10.c: Regenerate.
	* generated/maxval_r16.c: Regenerate.
	* generated/maxval_r17.c: Regenerate.
	* generated/maxval_r4.c: Regenerate.
	* generated/maxval_r8.c: Regenerate.
	* generated/minloc1_16_i1.c: Regenerate.
	* generated/minloc1_16_i16.c: Regenerate.
	* generated/minloc1_16_i2.c: Regenerate.
	* generated/minloc1_16_i4.c: Regenerate.
	* generated/minloc1_16_i8.c: Regenerate.
	* generated/minloc1_16_r10.c: Regenerate.
	* generated/minloc1_16_r16.c: Regenerate.
	* generated/minloc1_16_r17.c: Regenerate.
	* generated/minloc1_16_r4.c: Regenerate.
	* generated/minloc1_16_r8.c: Regenerate.
	* generated/minloc1_16_s1.c: Regenerate.
	* generated/minloc1_16_s4.c: Regenerate.
	* generated/minloc1_4_i1.c: Regenerate.
	* generated/minloc1_4_i16.c: Regenerate.
	* generated/minloc1_4_i2.c: Regenerate.
	* generated/minloc1_4_i4.c: Regenerate.
	* generated/minloc1_4_i8.c: Regenerate.
	* generated/minloc1_4_r10.c: Regenerate.
	* generated/minloc1_4_r16.c: Regenerate.
	* generated/minloc1_4_r17.c: Regenerate.
	* generated/minloc1_4_r4.c: Regenerate.
	* generated/minloc1_4_r8.c: Regenerate.
	* generated/minloc1_4_s1.c: Regenerate.
	* generated/minloc1_4_s4.c: Regenerate.
	* generated/minloc1_8_i1.c: Regenerate.
	* generated/minloc1_8_i16.c: Regenerate.
	* generated/minloc1_8_i2.c: Regenerate.
	* generated/minloc1_8_i4.c: Regenerate.
	* generated/minloc1_8_i8.c: Regenerate.
	* generated/minloc1_8_r10.c: Regenerate.
	* generated/minloc1_8_r16.c: Regenerate.
	* generated/minloc1_8_r17.c: Regenerate.
	* generated/minloc1_8_r4.c: Regenerate.
	* generated/minloc1_8_r8.c: Regenerate.
	* generated/minloc1_8_s1.c: Regenerate.
	* generated/minloc1_8_s4.c: Regenerate.
	* generated/minval1_s1.c: Regenerate.
	* generated/minval1_s4.c: Regenerate.
	* generated/minval_i1.c: Regenerate.
	* generated/minval_i16.c: Regenerate.
	* generated/minval_i2.c: Regenerate.
	* generated/minval_i4.c: Regenerate.
	* generated/minval_i8.c: Regenerate.
	* generated/minval_r10.c: Regenerate.
	* generated/minval_r16.c: Regenerate.
	* generated/minval_r17.c: Regenerate.
	* generated/minval_r4.c: Regenerate.
	* generated/minval_r8.c: Regenerate.
	* generated/product_c10.c: Regenerate.
	* generated/product_c16.c: Regenerate.
	* generated/product_c17.c: Regenerate.
	* generated/product_c4.c: Regenerate.
	* generated/product_c8.c: Regenerate.
	* generated/product_i1.c: Regenerate.
	* generated/product_i16.c: Regenerate.
	* generated/product_i2.c: Regenerate.
	* generated/product_i4.c: Regenerate.
	* generated/product_i8.c: Regenerate.
	* generated/product_r10.c: Regenerate.
	* generated/product_r16.c: Regenerate.
	* generated/product_r17.c: Regenerate.
	* generated/product_r4.c: Regenerate.
	* generated/product_r8.c: Regenerate.
	* generated/sum_c10.c: Regenerate.
	* generated/sum_c16.c: Regenerate.
	* generated/sum_c17.c: Regenerate.
	* generated/sum_c4.c: Regenerate.
	* generated/sum_c8.c: Regenerate.
	* generated/sum_i1.c: Regenerate.
	* generated/sum_i16.c: Regenerate.
	* generated/sum_i2.c: Regenerate.
	* generated/sum_i4.c: Regenerate.
	* generated/sum_i8.c: Regenerate.
	* generated/sum_r10.c: Regenerate.
	* generated/sum_r16.c: Regenerate.
	* generated/sum_r17.c: Regenerate.
	* generated/sum_r4.c: Regenerate.
	* generated/sum_r8.c: Regenerate.

gcc/testsuite/ChangeLog:

	* gfortran.dg/allocated_4.f90: New test.

4 files changed, 7 insertions, 17 deletions

diff --git a/libgfortran/m4/ifunction-s.m4 b/libgfortran/m4/ifunction-s.m4
index 16615aa290f..bc5ce55e81c 100644
--- a/libgfortran/m4/ifunction-s.m4
+++ b/libgfortran/m4/ifunction-s.m4
@@ -303,15 +303,13 @@ m'name`'rtype_qual`_'atype_code` ('rtype` * const restrict retarray,
       retarray->offset = 0;
       retarray->dtype.rank = rank;
 
+      retarray->base_addr = xmallocarray (alloc_size, sizeof (rtype_name));
       if (alloc_size == 0)
 	{
 	  /* Make sure we have a zero-sized array.  */
 	  GFC_DIMENSION_SET(retarray->dim[0], 0, -1, 1);
 	  return;
 	}
-      else
-	retarray->base_addr = xmallocarray (alloc_size, sizeof (rtype_name));
-
     }
   else
     {
@@ -467,14 +465,13 @@ s'name`'rtype_qual`_'atype_code` ('rtype` * const restrict retarray,
 
       alloc_size = GFC_DESCRIPTOR_STRIDE(retarray,rank-1) * extent[rank-1];
 
+      retarray->base_addr = xmallocarray (alloc_size, sizeof (rtype_name));
       if (alloc_size == 0)
 	{
 	  /* Make sure we have a zero-sized array.  */
 	  GFC_DIMENSION_SET(retarray->dim[0], 0, -1, 1);
 	  return;
 	}
-      else
-	retarray->base_addr = xmallocarray (alloc_size, sizeof (rtype_name));
     }
   else
     {
diff --git a/libgfortran/m4/ifunction-s2.m4 b/libgfortran/m4/ifunction-s2.m4
index 4d31c208e05..22ba00899d7 100644
--- a/libgfortran/m4/ifunction-s2.m4
+++ b/libgfortran/m4/ifunction-s2.m4
@@ -304,15 +304,13 @@ void
       retarray->offset = 0;
       retarray->dtype.rank = rank;
 
+      retarray->base_addr = xmallocarray (alloc_size, sizeof (rtype_name));
       if (alloc_size == 0)
 	{
 	  /* Make sure we have a zero-sized array.  */
 	  GFC_DIMENSION_SET(retarray->dim[0], 0, -1, 1);
 	  return;
 	}
-      else
-	retarray->base_addr = xmallocarray (alloc_size, sizeof (rtype_name));
-
     }
   else
     {
@@ -468,14 +466,13 @@ void
       alloc_size = GFC_DESCRIPTOR_STRIDE(retarray,rank-1) * extent[rank-1]
       		 * string_len;
 
+      retarray->base_addr = xmallocarray (alloc_size, sizeof (rtype_name));
       if (alloc_size == 0)
 	{
 	  /* Make sure we have a zero-sized array.  */
 	  GFC_DIMENSION_SET(retarray->dim[0], 0, -1, 1);
 	  return;
 	}
-      else
-	retarray->base_addr = xmallocarray (alloc_size, sizeof (rtype_name));
     }
   else
     {
diff --git a/libgfortran/m4/ifunction.m4 b/libgfortran/m4/ifunction.m4
index c64217ec5db..c80aa86c890 100644
--- a/libgfortran/m4/ifunction.m4
+++ b/libgfortran/m4/ifunction.m4
@@ -291,15 +291,13 @@ m'name`'rtype_qual`_'atype_code` ('rtype` * const restrict retarray,
       retarray->offset = 0;
       retarray->dtype.rank = rank;
 
+      retarray->base_addr = xmallocarray (alloc_size, sizeof (rtype_name));
       if (alloc_size == 0)
 	{
 	  /* Make sure we have a zero-sized array.  */
 	  GFC_DIMENSION_SET(retarray->dim[0], 0, -1, 1);
 	  return;
 	}
-      else
-	retarray->base_addr = xmallocarray (alloc_size, sizeof (rtype_name));
-
     }
   else
     {
@@ -455,14 +453,13 @@ void
 
       alloc_size = GFC_DESCRIPTOR_STRIDE(retarray,rank-1) * extent[rank-1];
 
+      retarray->base_addr = xmallocarray (alloc_size, sizeof (rtype_name));
       if (alloc_size == 0)
 	{
 	  /* Make sure we have a zero-sized array.  */
 	  GFC_DIMENSION_SET(retarray->dim[0], 0, -1, 1);
 	  return;
 	}
-      else
-	retarray->base_addr = xmallocarray (alloc_size, sizeof (rtype_name));
     }
   else
     {
diff --git a/libgfortran/m4/ifunction_logical.m4 b/libgfortran/m4/ifunction_logical.m4
index 0568387e343..cb576f3472e 100644
--- a/libgfortran/m4/ifunction_logical.m4
+++ b/libgfortran/m4/ifunction_logical.m4
@@ -91,14 +91,13 @@ name`'rtype_qual`_'atype_code (rtype * const restrict retarray,
 
       alloc_size = GFC_DESCRIPTOR_STRIDE(retarray,rank-1) * extent[rank-1];
 
+      retarray->base_addr = xmallocarray (alloc_size, sizeof (rtype_name));
       if (alloc_size == 0)
 	{
 	  /* Make sure we have a zero-sized array.  */
 	  GFC_DIMENSION_SET(retarray->dim[0], 0, -1, 1);
 	  return;
 	}
-      else
-	retarray->base_addr = xmallocarray (alloc_size, sizeof (rtype_name));
     }
   else
     {