memory.c (internal_malloc_size): If size is zero, allocate a single byte.

2011-07-05  Thomas Koenig  <tkoenig@gcc.gnu.org>

	* runtime/memory.c (internal_malloc_size):  If size is zero,
	allocate a single byte.
	* m4/pack.m4 (pack_'rtype_code`):  Don't check for zero size
	for the argument of internal_malloc_size.
	* m4/spread.m4 (spread_'rtype_code`):  Likewise.
	* m4/eoshift1.m4 (eoshift1):  Don't allocate twice.  Don't check
	for zero size for the argument of internal_malloc_size.
	* m4/eoshift3.m4: Don't check for zero size for the argument of
	internal_malloc_size.
	* intrinsics/pack_generic.c (pack_internal):  Likewise.
	(pack_s_internal):  Likewise.
	* intrinsics/cshift0.c (cshift0):  Likewise.
	* intrinsics/spread_generic.c (spread_internal):  Likewise.
	* intrinsics/eoshift0.c (eoshift0):  Likewise.
	* intrinsics/eoshift2.c (eoshift2):  Likewise.
	* generated/eoshift1_16.c: Regenerated.
	* generated/eoshift1_4.c: Regenerated.
	* generated/eoshift1_8.c: Regenerated.
	* generated/eoshift3_16.c: Regenerated.
	* generated/eoshift3_4.c: Regenerated.
	* generated/eoshift3_8.c: Regenerated.
	* generated/pack_c10.c: Regenerated.
	* generated/pack_c16.c: Regenerated.
	* generated/pack_c4.c: Regenerated.
	* generated/pack_c8.c: Regenerated.
	* generated/pack_i16.c: Regenerated.
	* generated/pack_i1.c: Regenerated.
	* generated/pack_i2.c: Regenerated.
	* generated/pack_i4.c: Regenerated.
	* generated/pack_i8.c: Regenerated.
	* generated/pack_r10.c: Regenerated.
	* generated/pack_r16.c: Regenerated.
	* generated/pack_r4.c: Regenerated.
	* generated/pack_r8.c: Regenerated.
	* generated/spread_c10.c: Regenerated.
	* generated/spread_c16.c: Regenerated.
	* generated/spread_c4.c: Regenerated.
	* generated/spread_c8.c: Regenerated.
	* generated/spread_i16.c: Regenerated.
	* generated/spread_i1.c: Regenerated.
	* generated/spread_i2.c: Regenerated.
	* generated/spread_i4.c: Regenerated.
	* generated/spread_i8.c: Regenerated.
	* generated/spread_r10.c: Regenerated.
	* generated/spread_r16.c: Regenerated.
	* generated/spread_r4.c: Regenerated.
	* generated/spread_r8.c: Regenerated.

From-SVN: r175880

libgfortran/ChangeLog

@@ -1,3 +1,53 @@
+2011-07-05  Thomas Koenig  <tkoenig@gcc.gnu.org>
+
+	* runtime/memory.c (internal_malloc_size):  If size is zero,
+	allocate a single byte.
+	* m4/pack.m4 (pack_'rtype_code`):  Don't check for zero size
+	for the argument of internal_malloc_size.
+	* m4/spread.m4 (spread_'rtype_code`):  Likewise.
+	* m4/eoshift1.m4 (eoshift1):  Don't allocate twice.  Don't check
+	for zero size for the argument of internal_malloc_size.
+	* m4/eoshift3.m4: Don't check for zero size for the argument of
+	internal_malloc_size.
+	* intrinsics/pack_generic.c (pack_internal):  Likewise.
+	(pack_s_internal):  Likewise.
+	* intrinsics/cshift0.c (cshift0):  Likewise.
+	* intrinsics/spread_generic.c (spread_internal):  Likewise.
+	* intrinsics/eoshift0.c (eoshift0):  Likewise.
+	* intrinsics/eoshift2.c (eoshift2):  Likewise.
+	* generated/eoshift1_16.c: Regenerated.
+	* generated/eoshift1_4.c: Regenerated.
+	* generated/eoshift1_8.c: Regenerated.
+	* generated/eoshift3_16.c: Regenerated.
+	* generated/eoshift3_4.c: Regenerated.
+	* generated/eoshift3_8.c: Regenerated.
+	* generated/pack_c10.c: Regenerated.
+	* generated/pack_c16.c: Regenerated.
+	* generated/pack_c4.c: Regenerated.
+	* generated/pack_c8.c: Regenerated.
+	* generated/pack_i16.c: Regenerated.
+	* generated/pack_i1.c: Regenerated.
+	* generated/pack_i2.c: Regenerated.
+	* generated/pack_i4.c: Regenerated.
+	* generated/pack_i8.c: Regenerated.
+	* generated/pack_r10.c: Regenerated.
+	* generated/pack_r16.c: Regenerated.
+	* generated/pack_r4.c: Regenerated.
+	* generated/pack_r8.c: Regenerated.
+	* generated/spread_c10.c: Regenerated.
+	* generated/spread_c16.c: Regenerated.
+	* generated/spread_c4.c: Regenerated.
+	* generated/spread_c8.c: Regenerated.
+	* generated/spread_i16.c: Regenerated.
+	* generated/spread_i1.c: Regenerated.
+	* generated/spread_i2.c: Regenerated.
+	* generated/spread_i4.c: Regenerated.
+	* generated/spread_i8.c: Regenerated.
+	* generated/spread_r10.c: Regenerated.
+	* generated/spread_r16.c: Regenerated.
+	* generated/spread_r4.c: Regenerated.
+	* generated/spread_r8.c: Regenerated.
+
 2011-06-28  Thomas Koenig  <tkoenig@gcc.gnu.org>
 
 	PR fortran/49479

libgfortran/generated/eoshift1_16.c

@@ -88,7 +88,6 @@ eoshift1 (gfc_array_char * const restrict ret,
     {
       int i;
 
-      ret->data = internal_malloc_size (size * arraysize);
       ret->offset = 0;
       ret->dtype = array->dtype;
       for (i = 0; i < GFC_DESCRIPTOR_RANK (array); i++)
@@ -106,10 +105,8 @@ eoshift1 (gfc_array_char * const restrict ret,
 	  GFC_DIMENSION_SET(ret->dim[i], 0, ub, str);
 
         }
-      if (arraysize > 0)
-	ret->data = internal_malloc_size (size * arraysize);
-      else
-	ret->data = internal_malloc_size (1);
+      /* internal_malloc_size allocates a single byte for zero size.  */
+      ret->data = internal_malloc_size (size * arraysize);
 
     }
   else if (unlikely (compile_options.bounds_check))

libgfortran/generated/eoshift1_4.c

@@ -88,7 +88,6 @@ eoshift1 (gfc_array_char * const restrict ret,
     {
       int i;
 
-      ret->data = internal_malloc_size (size * arraysize);
       ret->offset = 0;
       ret->dtype = array->dtype;
       for (i = 0; i < GFC_DESCRIPTOR_RANK (array); i++)
@@ -106,10 +105,8 @@ eoshift1 (gfc_array_char * const restrict ret,
 	  GFC_DIMENSION_SET(ret->dim[i], 0, ub, str);
 
         }
-      if (arraysize > 0)
-	ret->data = internal_malloc_size (size * arraysize);
-      else
-	ret->data = internal_malloc_size (1);
+      /* internal_malloc_size allocates a single byte for zero size.  */
+      ret->data = internal_malloc_size (size * arraysize);
 
     }
   else if (unlikely (compile_options.bounds_check))

libgfortran/generated/eoshift1_8.c

@@ -88,7 +88,6 @@ eoshift1 (gfc_array_char * const restrict ret,
     {
       int i;
 
-      ret->data = internal_malloc_size (size * arraysize);
       ret->offset = 0;
       ret->dtype = array->dtype;
       for (i = 0; i < GFC_DESCRIPTOR_RANK (array); i++)
@@ -106,10 +105,8 @@ eoshift1 (gfc_array_char * const restrict ret,
 	  GFC_DIMENSION_SET(ret->dim[i], 0, ub, str);
 
         }
-      if (arraysize > 0)
-	ret->data = internal_malloc_size (size * arraysize);
-      else
-	ret->data = internal_malloc_size (1);
+      /* internal_malloc_size allocates a single byte for zero size.  */
+      ret->data = internal_malloc_size (size * arraysize);
 
     }
   else if (unlikely (compile_options.bounds_check))

libgfortran/generated/eoshift3_16.c

@@ -107,10 +107,8 @@ eoshift3 (gfc_array_char * const restrict ret,
 	  GFC_DIMENSION_SET(ret->dim[i], 0, ub, str);
 
         }
-      if (arraysize > 0)
-	ret->data = internal_malloc_size (size * arraysize);
-      else
-	ret->data = internal_malloc_size (1);
+      /* internal_malloc_size allocates a single byte for zero size.  */
+      ret->data = internal_malloc_size (size * arraysize);
 
     }
   else if (unlikely (compile_options.bounds_check))

libgfortran/generated/eoshift3_4.c

@@ -107,10 +107,8 @@ eoshift3 (gfc_array_char * const restrict ret,
 	  GFC_DIMENSION_SET(ret->dim[i], 0, ub, str);
 
         }
-      if (arraysize > 0)
-	ret->data = internal_malloc_size (size * arraysize);
-      else
-	ret->data = internal_malloc_size (1);
+      /* internal_malloc_size allocates a single byte for zero size.  */
+      ret->data = internal_malloc_size (size * arraysize);
 
     }
   else if (unlikely (compile_options.bounds_check))

libgfortran/generated/eoshift3_8.c

@@ -107,10 +107,8 @@ eoshift3 (gfc_array_char * const restrict ret,
 	  GFC_DIMENSION_SET(ret->dim[i], 0, ub, str);
 
         }
-      if (arraysize > 0)
-	ret->data = internal_malloc_size (size * arraysize);
-      else
-	ret->data = internal_malloc_size (1);
+      /* internal_malloc_size allocates a single byte for zero size.  */
+      ret->data = internal_malloc_size (size * arraysize);
 
     }
   else if (unlikely (compile_options.bounds_check))

libgfortran/generated/pack_c10.c

@@ -166,14 +166,12 @@ pack_c10 (gfc_array_c10 *ret, const gfc_array_c10 *array,
 	  GFC_DIMENSION_SET(ret->dim[0], 0, total-1, 1);
 
 	  ret->offset = 0;
+
+	  /* internal_malloc_size allocates a single byte for zero size.  */
+	  ret->data = internal_malloc_size (sizeof (GFC_COMPLEX_10) * total);
+
 	  if (total == 0)
-	    {
-	      /* In this case, nothing remains to be done.  */
-	      ret->data = internal_malloc_size (1);
-	      return;
-	    }
-	  else
-	    ret->data = internal_malloc_size (sizeof (GFC_COMPLEX_10) * total);
+	    return;
 	}
       else 
 	{

libgfortran/generated/pack_c16.c

@@ -166,14 +166,12 @@ pack_c16 (gfc_array_c16 *ret, const gfc_array_c16 *array,
 	  GFC_DIMENSION_SET(ret->dim[0], 0, total-1, 1);
 
 	  ret->offset = 0;
+
+	  /* internal_malloc_size allocates a single byte for zero size.  */
+	  ret->data = internal_malloc_size (sizeof (GFC_COMPLEX_16) * total);
+
 	  if (total == 0)
-	    {
-	      /* In this case, nothing remains to be done.  */
-	      ret->data = internal_malloc_size (1);
-	      return;
-	    }
-	  else
-	    ret->data = internal_malloc_size (sizeof (GFC_COMPLEX_16) * total);
+	    return;
 	}
       else 
 	{

libgfortran/generated/pack_c4.c

@@ -166,14 +166,12 @@ pack_c4 (gfc_array_c4 *ret, const gfc_array_c4 *array,
 	  GFC_DIMENSION_SET(ret->dim[0], 0, total-1, 1);
 
 	  ret->offset = 0;
+
+	  /* internal_malloc_size allocates a single byte for zero size.  */
+	  ret->data = internal_malloc_size (sizeof (GFC_COMPLEX_4) * total);
+
 	  if (total == 0)
-	    {
-	      /* In this case, nothing remains to be done.  */
-	      ret->data = internal_malloc_size (1);
-	      return;
-	    }
-	  else
-	    ret->data = internal_malloc_size (sizeof (GFC_COMPLEX_4) * total);
+	    return;
 	}
       else 
 	{

libgfortran/generated/pack_c8.c

@@ -166,14 +166,12 @@ pack_c8 (gfc_array_c8 *ret, const gfc_array_c8 *array,
 	  GFC_DIMENSION_SET(ret->dim[0], 0, total-1, 1);
 
 	  ret->offset = 0;
+
+	  /* internal_malloc_size allocates a single byte for zero size.  */
+	  ret->data = internal_malloc_size (sizeof (GFC_COMPLEX_8) * total);
+
 	  if (total == 0)
-	    {
-	      /* In this case, nothing remains to be done.  */
-	      ret->data = internal_malloc_size (1);
-	      return;
-	    }
-	  else
-	    ret->data = internal_malloc_size (sizeof (GFC_COMPLEX_8) * total);
+	    return;
 	}
       else 
 	{

libgfortran/generated/pack_i1.c

@@ -166,14 +166,12 @@ pack_i1 (gfc_array_i1 *ret, const gfc_array_i1 *array,
 	  GFC_DIMENSION_SET(ret->dim[0], 0, total-1, 1);
 
 	  ret->offset = 0;
+
+	  /* internal_malloc_size allocates a single byte for zero size.  */
+	  ret->data = internal_malloc_size (sizeof (GFC_INTEGER_1) * total);
+
 	  if (total == 0)
-	    {
-	      /* In this case, nothing remains to be done.  */
-	      ret->data = internal_malloc_size (1);
-	      return;
-	    }
-	  else
-	    ret->data = internal_malloc_size (sizeof (GFC_INTEGER_1) * total);
+	    return;
 	}
       else 
 	{

libgfortran/generated/pack_i16.c

@@ -166,14 +166,12 @@ pack_i16 (gfc_array_i16 *ret, const gfc_array_i16 *array,
 	  GFC_DIMENSION_SET(ret->dim[0], 0, total-1, 1);
 
 	  ret->offset = 0;
+
+	  /* internal_malloc_size allocates a single byte for zero size.  */
+	  ret->data = internal_malloc_size (sizeof (GFC_INTEGER_16) * total);
+
 	  if (total == 0)
-	    {
-	      /* In this case, nothing remains to be done.  */
-	      ret->data = internal_malloc_size (1);
-	      return;
-	    }
-	  else
-	    ret->data = internal_malloc_size (sizeof (GFC_INTEGER_16) * total);
+	    return;
 	}
       else 
 	{

libgfortran/generated/pack_i2.c

@@ -166,14 +166,12 @@ pack_i2 (gfc_array_i2 *ret, const gfc_array_i2 *array,
 	  GFC_DIMENSION_SET(ret->dim[0], 0, total-1, 1);
 
 	  ret->offset = 0;
+
+	  /* internal_malloc_size allocates a single byte for zero size.  */
+	  ret->data = internal_malloc_size (sizeof (GFC_INTEGER_2) * total);
+
 	  if (total == 0)
-	    {
-	      /* In this case, nothing remains to be done.  */
-	      ret->data = internal_malloc_size (1);
-	      return;
-	    }
-	  else
-	    ret->data = internal_malloc_size (sizeof (GFC_INTEGER_2) * total);
+	    return;
 	}
       else 
 	{

libgfortran/generated/pack_i4.c

@@ -166,14 +166,12 @@ pack_i4 (gfc_array_i4 *ret, const gfc_array_i4 *array,
 	  GFC_DIMENSION_SET(ret->dim[0], 0, total-1, 1);
 
 	  ret->offset = 0;
+
+	  /* internal_malloc_size allocates a single byte for zero size.  */
+	  ret->data = internal_malloc_size (sizeof (GFC_INTEGER_4) * total);
+
 	  if (total == 0)
-	    {
-	      /* In this case, nothing remains to be done.  */
-	      ret->data = internal_malloc_size (1);
-	      return;
-	    }
-	  else
-	    ret->data = internal_malloc_size (sizeof (GFC_INTEGER_4) * total);
+	    return;
 	}
       else 
 	{

libgfortran/generated/pack_i8.c

@@ -166,14 +166,12 @@ pack_i8 (gfc_array_i8 *ret, const gfc_array_i8 *array,
 	  GFC_DIMENSION_SET(ret->dim[0], 0, total-1, 1);
 
 	  ret->offset = 0;
+
+	  /* internal_malloc_size allocates a single byte for zero size.  */
+	  ret->data = internal_malloc_size (sizeof (GFC_INTEGER_8) * total);
+
 	  if (total == 0)
-	    {
-	      /* In this case, nothing remains to be done.  */
-	      ret->data = internal_malloc_size (1);
-	      return;
-	    }
-	  else
-	    ret->data = internal_malloc_size (sizeof (GFC_INTEGER_8) * total);
+	    return;
 	}
       else 
 	{

libgfortran/generated/pack_r10.c

@@ -166,14 +166,12 @@ pack_r10 (gfc_array_r10 *ret, const gfc_array_r10 *array,
 	  GFC_DIMENSION_SET(ret->dim[0], 0, total-1, 1);
 
 	  ret->offset = 0;
+
+	  /* internal_malloc_size allocates a single byte for zero size.  */
+	  ret->data = internal_malloc_size (sizeof (GFC_REAL_10) * total);
+
 	  if (total == 0)
-	    {
-	      /* In this case, nothing remains to be done.  */
-	      ret->data = internal_malloc_size (1);
-	      return;
-	    }
-	  else
-	    ret->data = internal_malloc_size (sizeof (GFC_REAL_10) * total);
+	    return;
 	}
       else 
 	{

libgfortran/generated/pack_r16.c

@@ -166,14 +166,12 @@ pack_r16 (gfc_array_r16 *ret, const gfc_array_r16 *array,
 	  GFC_DIMENSION_SET(ret->dim[0], 0, total-1, 1);
 
 	  ret->offset = 0;
+
+	  /* internal_malloc_size allocates a single byte for zero size.  */
+	  ret->data = internal_malloc_size (sizeof (GFC_REAL_16) * total);
+
 	  if (total == 0)
-	    {
-	      /* In this case, nothing remains to be done.  */
-	      ret->data = internal_malloc_size (1);
-	      return;
-	    }
-	  else
-	    ret->data = internal_malloc_size (sizeof (GFC_REAL_16) * total);
+	    return;
 	}
       else 
 	{

libgfortran/generated/pack_r4.c

@@ -166,14 +166,12 @@ pack_r4 (gfc_array_r4 *ret, const gfc_array_r4 *array,
 	  GFC_DIMENSION_SET(ret->dim[0], 0, total-1, 1);
 
 	  ret->offset = 0;
+
+	  /* internal_malloc_size allocates a single byte for zero size.  */
+	  ret->data = internal_malloc_size (sizeof (GFC_REAL_4) * total);
+
 	  if (total == 0)
-	    {
-	      /* In this case, nothing remains to be done.  */
-	      ret->data = internal_malloc_size (1);
-	      return;
-	    }
-	  else
-	    ret->data = internal_malloc_size (sizeof (GFC_REAL_4) * total);
+	    return;
 	}
       else 
 	{

libgfortran/generated/pack_r8.c

@@ -166,14 +166,12 @@ pack_r8 (gfc_array_r8 *ret, const gfc_array_r8 *array,
 	  GFC_DIMENSION_SET(ret->dim[0], 0, total-1, 1);
 
 	  ret->offset = 0;
+
+	  /* internal_malloc_size allocates a single byte for zero size.  */
+	  ret->data = internal_malloc_size (sizeof (GFC_REAL_8) * total);
+
 	  if (total == 0)
-	    {
-	      /* In this case, nothing remains to be done.  */
-	      ret->data = internal_malloc_size (1);
-	      return;
-	    }
-	  else
-	    ret->data = internal_malloc_size (sizeof (GFC_REAL_8) * total);
+	    return;
 	}
       else 
 	{

libgfortran/generated/spread_c10.c

@@ -100,13 +100,11 @@ spread_c10 (gfc_array_c10 *ret, const gfc_array_c10 *source,
 	  GFC_DIMENSION_SET(ret->dim[n], 0, ub, stride);
 	}
       ret->offset = 0;
-      if (rs > 0)
-        ret->data = internal_malloc_size (rs * sizeof(GFC_COMPLEX_10));
-      else
-	{
-	  ret->data = internal_malloc_size (1);
-	  return;
-	}
+
+      /* internal_malloc_size allocates a single byte for zero size.  */
+      ret->data = internal_malloc_size (rs * sizeof(GFC_COMPLEX_10));
+      if (rs <= 0)
+        return;
     }
   else
     {

libgfortran/generated/spread_c16.c

@@ -100,13 +100,11 @@ spread_c16 (gfc_array_c16 *ret, const gfc_array_c16 *source,
 	  GFC_DIMENSION_SET(ret->dim[n], 0, ub, stride);
 	}
       ret->offset = 0;
-      if (rs > 0)
-        ret->data = internal_malloc_size (rs * sizeof(GFC_COMPLEX_16));
-      else
-	{
-	  ret->data = internal_malloc_size (1);
-	  return;
-	}
+
+      /* internal_malloc_size allocates a single byte for zero size.  */
+      ret->data = internal_malloc_size (rs * sizeof(GFC_COMPLEX_16));
+      if (rs <= 0)
+        return;
     }
   else
     {

libgfortran/generated/spread_c4.c

@@ -100,13 +100,11 @@ spread_c4 (gfc_array_c4 *ret, const gfc_array_c4 *source,
 	  GFC_DIMENSION_SET(ret->dim[n], 0, ub, stride);
 	}
       ret->offset = 0;
-      if (rs > 0)
-        ret->data = internal_malloc_size (rs * sizeof(GFC_COMPLEX_4));
-      else
-	{
-	  ret->data = internal_malloc_size (1);
-	  return;
-	}
+
+      /* internal_malloc_size allocates a single byte for zero size.  */
+      ret->data = internal_malloc_size (rs * sizeof(GFC_COMPLEX_4));
+      if (rs <= 0)
+        return;
     }
   else
     {

libgfortran/generated/spread_c8.c

@@ -100,13 +100,11 @@ spread_c8 (gfc_array_c8 *ret, const gfc_array_c8 *source,
 	  GFC_DIMENSION_SET(ret->dim[n], 0, ub, stride);
 	}
       ret->offset = 0;
-      if (rs > 0)
-        ret->data = internal_malloc_size (rs * sizeof(GFC_COMPLEX_8));
-      else
-	{
-	  ret->data = internal_malloc_size (1);
-	  return;
-	}
+
+      /* internal_malloc_size allocates a single byte for zero size.  */
+      ret->data = internal_malloc_size (rs * sizeof(GFC_COMPLEX_8));
+      if (rs <= 0)
+        return;
     }
   else
     {

libgfortran/generated/spread_i1.c

@@ -100,13 +100,11 @@ spread_i1 (gfc_array_i1 *ret, const gfc_array_i1 *source,
 	  GFC_DIMENSION_SET(ret->dim[n], 0, ub, stride);
 	}
       ret->offset = 0;
-      if (rs > 0)
-        ret->data = internal_malloc_size (rs * sizeof(GFC_INTEGER_1));
-      else
-	{
-	  ret->data = internal_malloc_size (1);
-	  return;
-	}
+
+      /* internal_malloc_size allocates a single byte for zero size.  */
+      ret->data = internal_malloc_size (rs * sizeof(GFC_INTEGER_1));
+      if (rs <= 0)
+        return;
     }
   else
     {

libgfortran/generated/spread_i16.c

@@ -100,13 +100,11 @@ spread_i16 (gfc_array_i16 *ret, const gfc_array_i16 *source,
 	  GFC_DIMENSION_SET(ret->dim[n], 0, ub, stride);
 	}
       ret->offset = 0;
-      if (rs > 0)
-        ret->data = internal_malloc_size (rs * sizeof(GFC_INTEGER_16));
-      else
-	{
-	  ret->data = internal_malloc_size (1);
-	  return;
-	}
+
+      /* internal_malloc_size allocates a single byte for zero size.  */
+      ret->data = internal_malloc_size (rs * sizeof(GFC_INTEGER_16));
+      if (rs <= 0)
+        return;
     }
   else
     {

libgfortran/generated/spread_i2.c

@@ -100,13 +100,11 @@ spread_i2 (gfc_array_i2 *ret, const gfc_array_i2 *source,
 	  GFC_DIMENSION_SET(ret->dim[n], 0, ub, stride);
 	}
       ret->offset = 0;
-      if (rs > 0)
-        ret->data = internal_malloc_size (rs * sizeof(GFC_INTEGER_2));
-      else
-	{
-	  ret->data = internal_malloc_size (1);
-	  return;
-	}
+
+      /* internal_malloc_size allocates a single byte for zero size.  */
+      ret->data = internal_malloc_size (rs * sizeof(GFC_INTEGER_2));
+      if (rs <= 0)
+        return;
     }
   else
     {

libgfortran/generated/spread_i4.c

@@ -100,13 +100,11 @@ spread_i4 (gfc_array_i4 *ret, const gfc_array_i4 *source,
 	  GFC_DIMENSION_SET(ret->dim[n], 0, ub, stride);
 	}
       ret->offset = 0;
-      if (rs > 0)
-        ret->data = internal_malloc_size (rs * sizeof(GFC_INTEGER_4));
-      else
-	{
-	  ret->data = internal_malloc_size (1);
-	  return;
-	}
+
+      /* internal_malloc_size allocates a single byte for zero size.  */
+      ret->data = internal_malloc_size (rs * sizeof(GFC_INTEGER_4));
+      if (rs <= 0)
+        return;
     }
   else
     {

libgfortran/generated/spread_i8.c

@@ -100,13 +100,11 @@ spread_i8 (gfc_array_i8 *ret, const gfc_array_i8 *source,
 	  GFC_DIMENSION_SET(ret->dim[n], 0, ub, stride);
 	}
       ret->offset = 0;
-      if (rs > 0)
-        ret->data = internal_malloc_size (rs * sizeof(GFC_INTEGER_8));
-      else
-	{
-	  ret->data = internal_malloc_size (1);
-	  return;
-	}
+
+      /* internal_malloc_size allocates a single byte for zero size.  */
+      ret->data = internal_malloc_size (rs * sizeof(GFC_INTEGER_8));
+      if (rs <= 0)
+        return;
     }
   else
     {

libgfortran/generated/spread_r10.c

@@ -100,13 +100,11 @@ spread_r10 (gfc_array_r10 *ret, const gfc_array_r10 *source,
 	  GFC_DIMENSION_SET(ret->dim[n], 0, ub, stride);
 	}
       ret->offset = 0;
-      if (rs > 0)
-        ret->data = internal_malloc_size (rs * sizeof(GFC_REAL_10));
-      else
-	{
-	  ret->data = internal_malloc_size (1);
-	  return;
-	}
+
+      /* internal_malloc_size allocates a single byte for zero size.  */
+      ret->data = internal_malloc_size (rs * sizeof(GFC_REAL_10));
+      if (rs <= 0)
+        return;
     }
   else
     {

libgfortran/generated/spread_r16.c

@@ -100,13 +100,11 @@ spread_r16 (gfc_array_r16 *ret, const gfc_array_r16 *source,
 	  GFC_DIMENSION_SET(ret->dim[n], 0, ub, stride);
 	}
       ret->offset = 0;
-      if (rs > 0)
-        ret->data = internal_malloc_size (rs * sizeof(GFC_REAL_16));
-      else
-	{
-	  ret->data = internal_malloc_size (1);
-	  return;
-	}
+
+      /* internal_malloc_size allocates a single byte for zero size.  */
+      ret->data = internal_malloc_size (rs * sizeof(GFC_REAL_16));
+      if (rs <= 0)
+        return;
     }
   else
     {

libgfortran/generated/spread_r4.c

@@ -100,13 +100,11 @@ spread_r4 (gfc_array_r4 *ret, const gfc_array_r4 *source,
 	  GFC_DIMENSION_SET(ret->dim[n], 0, ub, stride);
 	}
       ret->offset = 0;
-      if (rs > 0)
-        ret->data = internal_malloc_size (rs * sizeof(GFC_REAL_4));
-      else
-	{
-	  ret->data = internal_malloc_size (1);
-	  return;
-	}
+
+      /* internal_malloc_size allocates a single byte for zero size.  */
+      ret->data = internal_malloc_size (rs * sizeof(GFC_REAL_4));
+      if (rs <= 0)
+        return;
     }
   else
     {

libgfortran/generated/spread_r8.c

@@ -100,13 +100,11 @@ spread_r8 (gfc_array_r8 *ret, const gfc_array_r8 *source,
 	  GFC_DIMENSION_SET(ret->dim[n], 0, ub, stride);
 	}
       ret->offset = 0;
-      if (rs > 0)
-        ret->data = internal_malloc_size (rs * sizeof(GFC_REAL_8));
-      else
-	{
-	  ret->data = internal_malloc_size (1);
-	  return;
-	}
+
+      /* internal_malloc_size allocates a single byte for zero size.  */
+      ret->data = internal_malloc_size (rs * sizeof(GFC_REAL_8));
+      if (rs <= 0)
+        return;
     }
   else
     {

libgfortran/intrinsics/cshift0.c

@@ -79,10 +79,8 @@ cshift0 (gfc_array_char * ret, const gfc_array_char * array,
 	  GFC_DIMENSION_SET(ret->dim[i], 0, ub, str);
         }
 
-      if (arraysize > 0)
-	ret->data = internal_malloc_size (size * arraysize);
-      else
-	ret->data = internal_malloc_size (1);
+      /* internal_malloc_size allocates a single byte for zero size.  */
+      ret->data = internal_malloc_size (size * arraysize);
     }
   else if (unlikely (compile_options.bounds_check))
     {

libgfortran/intrinsics/eoshift0.c

@@ -86,11 +86,8 @@ eoshift0 (gfc_array_char * ret, const gfc_array_char * array,
 
         }
 
-      if (arraysize > 0)
-	ret->data = internal_malloc_size (size * arraysize);
-      else
-	ret->data = internal_malloc_size (1);
-
+      /* internal_malloc_size allocates a single byte for zero size.  */
+      ret->data = internal_malloc_size (size * arraysize);
     }
   else if (unlikely (compile_options.bounds_check))
     {

libgfortran/intrinsics/eoshift2.c

@@ -91,10 +91,8 @@ eoshift2 (gfc_array_char *ret, const gfc_array_char *array,
 
 	  GFC_DIMENSION_SET(ret->dim[i], 0, ub, str);
 
-	  if (arraysize > 0)
-	    ret->data = internal_malloc_size (size * arraysize);
-	  else
-	    ret->data = internal_malloc_size (1);
+          /* internal_malloc_size allocates a single byte for zero size.  */
+	  ret->data = internal_malloc_size (size * arraysize);
 
         }
     }

libgfortran/intrinsics/pack_generic.c

@@ -153,14 +153,11 @@ pack_internal (gfc_array_char *ret, const gfc_array_char *array,
 	  GFC_DIMENSION_SET(ret->dim[0], 0, total-1, 1);
 
 	  ret->offset = 0;
+	  /* internal_malloc_size allocates a single byte for zero size.  */
+	  ret->data = internal_malloc_size (size * total);
+
 	  if (total == 0)
-	    {
-	      /* In this case, nothing remains to be done.  */
-	      ret->data = internal_malloc_size (1);
-	      return;
-	    }
-	  else
-	    ret->data = internal_malloc_size (size * total);
+	    return;      /* In this case, nothing remains to be done.  */
 	}
       else 
 	{
@@ -523,13 +520,10 @@ pack_s_internal (gfc_array_char *ret, const gfc_array_char *array,
 
       ret->offset = 0;
 
+      ret->data = internal_malloc_size (size * total);
+
       if (total == 0)
-	{
-	  ret->data = internal_malloc_size (1);
-	  return;
-	}
-      else
-	ret->data = internal_malloc_size (size * total);
+	return;
     }
 
   rstride0 = GFC_DESCRIPTOR_STRIDE_BYTES(ret,0);

libgfortran/intrinsics/spread_generic.c

@@ -100,13 +100,10 @@ spread_internal (gfc_array_char *ret, const gfc_array_char *source,
 	  GFC_DIMENSION_SET(ret->dim[n], 0, ub, stride);
 	}
       ret->offset = 0;
-      if (rs > 0)
-        ret->data = internal_malloc_size (rs * size);
-      else
-	{
-	  ret->data = internal_malloc_size (1);
-	  return;
-	}
+      ret->data = internal_malloc_size (rs * size);
+
+      if (rs <= 0)
+	return;
     }
   else
     {

libgfortran/m4/eoshift1.m4

@@ -89,7 +89,6 @@ eoshift1 (gfc_array_char * const restrict ret,
     {
       int i;
 
-      ret->data = internal_malloc_size (size * arraysize);
       ret->offset = 0;
       ret->dtype = array->dtype;
       for (i = 0; i < GFC_DESCRIPTOR_RANK (array); i++)
@@ -107,10 +106,8 @@ eoshift1 (gfc_array_char * const restrict ret,
 	  GFC_DIMENSION_SET(ret->dim[i], 0, ub, str);
 
         }
-      if (arraysize > 0)
-	ret->data = internal_malloc_size (size * arraysize);
-      else
-	ret->data = internal_malloc_size (1);
+      /* internal_malloc_size allocates a single byte for zero size.  */
+      ret->data = internal_malloc_size (size * arraysize);
 
     }
   else if (unlikely (compile_options.bounds_check))

libgfortran/m4/eoshift3.m4

@@ -108,10 +108,8 @@ eoshift3 (gfc_array_char * const restrict ret,
 	  GFC_DIMENSION_SET(ret->dim[i], 0, ub, str);
 
         }
-      if (arraysize > 0)
-	ret->data = internal_malloc_size (size * arraysize);
-      else
-	ret->data = internal_malloc_size (1);
+      /* internal_malloc_size allocates a single byte for zero size.  */
+      ret->data = internal_malloc_size (size * arraysize);
 
     }
   else if (unlikely (compile_options.bounds_check))

libgfortran/m4/pack.m4

@@ -167,14 +167,12 @@ pack_'rtype_code` ('rtype` *ret, const 'rtype` *array,
 	  GFC_DIMENSION_SET(ret->dim[0], 0, total-1, 1);
 
 	  ret->offset = 0;
+
+	  /* internal_malloc_size allocates a single byte for zero size.  */
+	  ret->data = internal_malloc_size (sizeof ('rtype_name`) * total);
+
 	  if (total == 0)
-	    {
-	      /* In this case, nothing remains to be done.  */
-	      ret->data = internal_malloc_size (1);
-	      return;
-	    }
-	  else
-	    ret->data = internal_malloc_size (sizeof ('rtype_name`) * total);
+	    return;
 	}
       else 
 	{

libgfortran/m4/spread.m4

@@ -101,13 +101,11 @@ spread_'rtype_code` ('rtype` *ret, const 'rtype` *source,
 	  GFC_DIMENSION_SET(ret->dim[n], 0, ub, stride);
 	}
       ret->offset = 0;
-      if (rs > 0)
-        ret->data = internal_malloc_size (rs * sizeof('rtype_name`));
-      else
-	{
-	  ret->data = internal_malloc_size (1);
-	  return;
-	}
+
+      /* internal_malloc_size allocates a single byte for zero size.  */
+      ret->data = internal_malloc_size (rs * sizeof('rtype_name`));
+      if (rs <= 0)
+        return;
     }
   else
     {

libgfortran/runtime/memory.c

@@ -54,8 +54,8 @@ get_mem (size_t n)
 void *
 internal_malloc_size (size_t size)
 {
-  if (size == 0)
-    return NULL;
+  if (unlikely (size == 0))
+    size = 1;
 
   return get_mem (size);
 }