re PR fortran/60543 (Function with side effect removed by the optimizer.)

2014-03-18  Tobias Burnus  <burnus@net-b.de>

        PR fortran/60543
        PR fortran/60283
        * gfortran.h (gfc_unset_implicit_pure): New prototype.
        * resolve.c (gfc_unset_implicit_pure): New.
        (resolve_structure_cons, resolve_function,
        pure_subroutine): Use it.
        * decl.c (match_old_style_init, gfc_match_data,
        match_pointer_init, variable_decl): Ditto.
        * expr.c (gfc_check_pointer_assign): Ditto.
        * intrinsic.c (gfc_intrinsic_sub_interface): Ditto.
        * io.c (match_vtag, gfc_match_open, gfc_match_close,
        match_filepos, gfc_match_inquire, gfc_match_print,
        gfc_match_wait): Ditto.
        * match.c (gfc_match_critical, gfc_match_stopcode,
        lock_unlock_statement, sync_statement, gfc_match_allocate,
        gfc_match_deallocate): Ditto.
        * parse.c (decode_omp_directive): Ditto.
        * symbol.c (gfc_add_save): Ditto.

2014-03-18  Tobias Burnus  <burnus@net-b.de>

        PR fortran/60543
        PR fortran/60283
        * gfortran.dg/implicit_pure_4.f90: New.

From-SVN: r208687

gcc/fortran/ChangeLog

+2014-03-19  Tobias Burnus  <burnus@net-b.de>
+
+	PR fortran/60543
+	PR fortran/60283
+	* gfortran.h (gfc_unset_implicit_pure): New prototype.
+	* resolve.c (gfc_unset_implicit_pure): New.
+	(resolve_structure_cons, resolve_function,
+	pure_subroutine): Use it.
+	* decl.c (match_old_style_init, gfc_match_data,
+	match_pointer_init, variable_decl): Ditto.
+	* expr.c (gfc_check_pointer_assign): Ditto.
+	* intrinsic.c (gfc_intrinsic_sub_interface): Ditto.
+	* io.c (match_vtag, gfc_match_open, gfc_match_close,
+	match_filepos, gfc_match_inquire, gfc_match_print,
+	gfc_match_wait): Ditto.
+	* match.c (gfc_match_critical, gfc_match_stopcode,
+	lock_unlock_statement, sync_statement, gfc_match_allocate,
+	gfc_match_deallocate): Ditto.
+	* parse.c (decode_omp_directive): Ditto.
+	* symbol.c (gfc_add_save): Ditto.
+
 2014-03-18  Janus Weil  <janus@gcc.gnu.org>
 
 	PR fortran/55207

gcc/fortran/decl.c

@@ -510,9 +510,7 @@ match_old_style_init (const char *name)
       free (newdata);
       return MATCH_ERROR;
     }
-
-  if (gfc_implicit_pure (NULL))
-    gfc_current_ns->proc_name->attr.implicit_pure = 0;
+  gfc_unset_implicit_pure (gfc_current_ns->proc_name);
 
   /* Mark the variable as having appeared in a data statement.  */
   if (!gfc_add_data (&sym->attr, sym->name, &sym->declared_at))
@@ -571,9 +569,7 @@ gfc_match_data (void)
       gfc_error ("DATA statement at %C is not allowed in a PURE procedure");
       return MATCH_ERROR;
     }
-
-  if (gfc_implicit_pure (NULL))
-    gfc_current_ns->proc_name->attr.implicit_pure = 0;
+  gfc_unset_implicit_pure (gfc_current_ns->proc_name);
 
   return MATCH_YES;
 
@@ -1739,6 +1735,7 @@ match_pointer_init (gfc_expr **init, int procptr)
 		 "a PURE procedure");
       return MATCH_ERROR;
     }
+  gfc_unset_implicit_pure (gfc_current_ns->proc_name);
 
   /* Match NULL() initialization.  */
   m = gfc_match_null (init);
@@ -2046,6 +2043,10 @@ variable_decl (int elem)
 	      m = MATCH_ERROR;
 	    }
 
+	  if (current_attr.flavor != FL_PARAMETER
+	      && gfc_state_stack->state != COMP_DERIVED)
+	    gfc_unset_implicit_pure (gfc_current_ns->proc_name);
+
 	  if (m != MATCH_YES)
 	    goto cleanup;
 	}

gcc/fortran/expr.c

@@ -3704,8 +3704,7 @@ gfc_check_pointer_assign (gfc_expr *lvalue, gfc_expr *rvalue)
     }
 
   if (is_implicit_pure && gfc_impure_variable (rvalue->symtree->n.sym))
-    gfc_current_ns->proc_name->attr.implicit_pure = 0;
-
+    gfc_unset_implicit_pure (gfc_current_ns->proc_name);
 
   if (gfc_has_vector_index (rvalue))
     {

gcc/fortran/gfortran.h

@@ -2837,6 +2837,7 @@ void gfc_resolve_blocks (gfc_code *, gfc_namespace *);
 int gfc_impure_variable (gfc_symbol *);
 int gfc_pure (gfc_symbol *);
 int gfc_implicit_pure (gfc_symbol *);
+void gfc_unset_implicit_pure (gfc_symbol *);
 int gfc_elemental (gfc_symbol *);
 bool gfc_resolve_iterator (gfc_iterator *, bool, bool);
 bool find_forall_index (gfc_expr *, gfc_symbol *, int);

gcc/fortran/intrinsic.c

@@ -4404,13 +4404,16 @@ gfc_intrinsic_sub_interface (gfc_code *c, int error_flag)
       return MATCH_ERROR;
     }
 
-  if (gfc_pure (NULL) && !isym->pure)
+  if (!isym->pure && gfc_pure (NULL))
     {
       gfc_error ("Subroutine call to intrinsic '%s' at %L is not PURE", name,
 		 &c->loc);
       return MATCH_ERROR;
     }
 
+  if (!isym->pure)
+    gfc_unset_implicit_pure (NULL);
+
   c->resolved_sym->attr.noreturn = isym->noreturn;
 
   return MATCH_YES;

gcc/fortran/io.c

@@ -1305,7 +1305,8 @@ match_vtag (const io_tag *tag, gfc_expr **v)
       return MATCH_ERROR;
     }
 
-  if (gfc_pure (NULL) && gfc_impure_variable (result->symtree->n.sym))
+  bool impure = gfc_impure_variable (result->symtree->n.sym);
+  if (impure && gfc_pure (NULL))
     {
       gfc_error ("Variable %s cannot be assigned in PURE procedure at %C",
 		 tag->name);
@@ -1313,8 +1314,8 @@ match_vtag (const io_tag *tag, gfc_expr **v)
       return MATCH_ERROR;
     }
 
-  if (gfc_implicit_pure (NULL) && gfc_impure_variable (result->symtree->n.sym))
-    gfc_current_ns->proc_name->attr.implicit_pure = 0;
+  if (impure)
+    gfc_unset_implicit_pure (NULL);
 
   *v = result;
   return MATCH_YES;
@@ -1829,8 +1830,7 @@ gfc_match_open (void)
       goto cleanup;
     }
 
-  if (gfc_implicit_pure (NULL))
-    gfc_current_ns->proc_name->attr.implicit_pure = 0;
+  gfc_unset_implicit_pure (NULL);
 
   warn = (open->err || open->iostat) ? true : false;
 
@@ -2242,8 +2242,7 @@ gfc_match_close (void)
       goto cleanup;
     }
 
-  if (gfc_implicit_pure (NULL))
-    gfc_current_ns->proc_name->attr.implicit_pure = 0;
+  gfc_unset_implicit_pure (NULL);
 
   warn = (close->iostat || close->err) ? true : false;
 
@@ -2410,8 +2409,7 @@ done:
       goto cleanup;
     }
 
-  if (gfc_implicit_pure (NULL))
-    gfc_current_ns->proc_name->attr.implicit_pure = 0;
+  gfc_unset_implicit_pure (NULL);
 
   new_st.op = op;
   new_st.ext.filepos = fp;
@@ -3793,8 +3791,7 @@ gfc_match_print (void)
       return MATCH_ERROR;
     }
 
-  if (gfc_implicit_pure (NULL))
-    gfc_current_ns->proc_name->attr.implicit_pure = 0;
+  gfc_unset_implicit_pure (NULL);
 
   return MATCH_YES;
 }
@@ -3953,8 +3950,7 @@ gfc_match_inquire (void)
 	  return MATCH_ERROR;
 	}
 
-      if (gfc_implicit_pure (NULL))
-	gfc_current_ns->proc_name->attr.implicit_pure = 0;
+      gfc_unset_implicit_pure (NULL);
 
       new_st.block = gfc_get_code (EXEC_IOLENGTH);
       terminate_io (code);
@@ -4006,8 +4002,7 @@ gfc_match_inquire (void)
       goto cleanup;
     }
 
-  if (gfc_implicit_pure (NULL))
-    gfc_current_ns->proc_name->attr.implicit_pure = 0;
+  gfc_unset_implicit_pure (NULL);
   
   if (inquire->id != NULL && inquire->pending == NULL)
     {
@@ -4195,8 +4190,7 @@ gfc_match_wait (void)
       goto cleanup;
     }
 
-  if (gfc_implicit_pure (NULL))
-    gfc_current_ns->proc_name->attr.implicit_pure = 0;
+  gfc_unset_implicit_pure (NULL);
 
   new_st.op = EXEC_WAIT;
   new_st.ext.wait = wait;

gcc/fortran/match.c

@@ -1751,8 +1751,7 @@ gfc_match_critical (void)
       return MATCH_ERROR;
     }
 
-  if (gfc_implicit_pure (NULL))
-    gfc_current_ns->proc_name->attr.implicit_pure = 0;
+  gfc_unset_implicit_pure (NULL);
 
   if (!gfc_notify_std (GFC_STD_F2008, "CRITICAL statement at %C"))
     return MATCH_ERROR;
@@ -2676,8 +2675,7 @@ gfc_match_stopcode (gfc_statement st)
       goto cleanup;
     }
 
-  if (gfc_implicit_pure (NULL))
-    gfc_current_ns->proc_name->attr.implicit_pure = 0;
+  gfc_unset_implicit_pure (NULL);
 
   if (st == ST_STOP && gfc_find_state (COMP_CRITICAL))
     {
@@ -2814,8 +2812,7 @@ lock_unlock_statement (gfc_statement st)
       return MATCH_ERROR;
     }
 
-  if (gfc_implicit_pure (NULL))
-    gfc_current_ns->proc_name->attr.implicit_pure = 0;
+  gfc_unset_implicit_pure (NULL);
 
   if (gfc_option.coarray == GFC_FCOARRAY_NONE)
     {
@@ -3008,8 +3005,7 @@ sync_statement (gfc_statement st)
       return MATCH_ERROR;
     }
 
-  if (gfc_implicit_pure (NULL))
-    gfc_current_ns->proc_name->attr.implicit_pure = 0;
+  gfc_unset_implicit_pure (NULL);
 
   if (!gfc_notify_std (GFC_STD_F2008, "SYNC statement at %C"))
     return MATCH_ERROR;
@@ -3479,15 +3475,15 @@ gfc_match_allocate (void)
       if (gfc_check_do_variable (tail->expr->symtree))
 	goto cleanup;
 
-      if (gfc_pure (NULL) && gfc_impure_variable (tail->expr->symtree->n.sym))
+      bool impure = gfc_impure_variable (tail->expr->symtree->n.sym);
+      if (impure && gfc_pure (NULL))
 	{
 	  gfc_error ("Bad allocate-object at %C for a PURE procedure");
 	  goto cleanup;
 	}
 
-      if (gfc_implicit_pure (NULL)
-	    && gfc_impure_variable (tail->expr->symtree->n.sym))
-	gfc_current_ns->proc_name->attr.implicit_pure = 0;
+      if (impure)
+	gfc_unset_implicit_pure (NULL);
 
       if (tail->expr->ts.deferred)
 	{
@@ -3868,14 +3864,15 @@ gfc_match_deallocate (void)
 
       sym = tail->expr->symtree->n.sym;
 
-      if (gfc_pure (NULL) && gfc_impure_variable (sym))
+      bool impure = gfc_impure_variable (sym);
+      if (impure && gfc_pure (NULL))
 	{
 	  gfc_error ("Illegal allocate-object at %C for a PURE procedure");
 	  goto cleanup;
 	}
 
-      if (gfc_implicit_pure (NULL) && gfc_impure_variable (sym))
-	gfc_current_ns->proc_name->attr.implicit_pure = 0;
+      if (impure)
+	gfc_unset_implicit_pure (NULL);
 
       if (gfc_is_coarray (tail->expr)
 	  && gfc_find_state (COMP_DO_CONCURRENT))

gcc/fortran/parse.c

@@ -550,8 +550,7 @@ decode_omp_directive (void)
       return ST_NONE;
     }
 
-  if (gfc_implicit_pure (NULL))
-    gfc_current_ns->proc_name->attr.implicit_pure = 0;
+  gfc_unset_implicit_pure (NULL);
 
   old_locus = gfc_current_locus;
 

gcc/fortran/resolve.c

@@ -1328,9 +1328,10 @@ resolve_structure_cons (gfc_expr *expr, int init)
 	}
 
       /* F2003, C1272 (3).  */
-      if (gfc_pure (NULL) && cons->expr->expr_type == EXPR_VARIABLE
-	  && (gfc_impure_variable (cons->expr->symtree->n.sym)
-	      || gfc_is_coindexed (cons->expr)))
+      bool impure = cons->expr->expr_type == EXPR_VARIABLE
+		    && (gfc_impure_variable (cons->expr->symtree->n.sym)
+			|| gfc_is_coindexed (cons->expr));
+      if (impure && gfc_pure (NULL))
 	{
 	  t = false;
 	  gfc_error ("Invalid expression in the structure constructor for "
@@ -1338,12 +1339,8 @@ resolve_structure_cons (gfc_expr *expr, int init)
 		     comp->name, &cons->expr->where);
 	}
 
-      if (gfc_implicit_pure (NULL)
-	    && cons->expr->expr_type == EXPR_VARIABLE
-	    && (gfc_impure_variable (cons->expr->symtree->n.sym)
-		|| gfc_is_coindexed (cons->expr)))
-	gfc_current_ns->proc_name->attr.implicit_pure = 0;
-
+      if (impure)
+	gfc_unset_implicit_pure (NULL);
     }
 
   return t;
@@ -3006,8 +3003,7 @@ resolve_function (gfc_expr *expr)
 	  t = false;
 	}
 
-      if (gfc_implicit_pure (NULL))
-	gfc_current_ns->proc_name->attr.implicit_pure = 0;
+      gfc_unset_implicit_pure (NULL);
     }
 
   /* Functions without the RECURSIVE attribution are not allowed to
@@ -3072,8 +3068,7 @@ pure_subroutine (gfc_code *c, gfc_symbol *sym)
     gfc_error ("Subroutine call to '%s' at %L is not PURE", sym->name,
 	       &c->loc);
 
-  if (gfc_implicit_pure (NULL))
-    gfc_current_ns->proc_name->attr.implicit_pure = 0;
+  gfc_unset_implicit_pure (NULL);
 }
 
 
@@ -13927,6 +13922,33 @@ gfc_implicit_pure (gfc_symbol *sym)
 }
 
 
+void
+gfc_unset_implicit_pure (gfc_symbol *sym)
+{
+  gfc_namespace *ns;
+
+  if (sym == NULL)
+    {
+      /* Check if the current procedure is implicit_pure.  Walk up
+	 the procedure list until we find a procedure.  */
+      for (ns = gfc_current_ns; ns; ns = ns->parent)
+	{
+	  sym = ns->proc_name;
+	  if (sym == NULL)
+	    return;
+
+	  if (sym->attr.flavor == FL_PROCEDURE)
+	    break;
+	}
+    }
+
+  if (sym->attr.flavor == FL_PROCEDURE)
+    sym->attr.implicit_pure = 0;
+  else
+    sym->attr.pure = 0;
+}
+
+
 /* Test whether the current procedure is elemental or not.  */
 
 int

gcc/fortran/symbol.c

@@ -1114,8 +1114,8 @@ gfc_add_save (symbol_attribute *attr, save_state s, const char *name,
       return false;
     }
 
-  if (s == SAVE_EXPLICIT && gfc_implicit_pure (NULL))
-    gfc_current_ns->proc_name->attr.implicit_pure = 0;
+  if (s == SAVE_EXPLICIT)
+    gfc_unset_implicit_pure (NULL);
 
   if (s == SAVE_EXPLICIT && attr->save == SAVE_EXPLICIT)
     {

gcc/testsuite/ChangeLog

+2014-03-19  Tobias Burnus  <burnus@net-b.de>
+
+	PR fortran/60543
+	PR fortran/60283
+	* gfortran.dg/implicit_pure_4.f90: New.
+
 2014-03-19  Paolo Carlini  <paolo.carlini@oracle.com>
 
 	PR c++/51474

gcc/testsuite/gfortran.dg/implicit_pure_4.f90

+! { dg-do compile }
+!
+! PR fortran/60543
+! PR fortran/60283
+!
+module m
+contains
+  REAL(8) FUNCTION random()
+    CALL RANDOM_NUMBER(random)
+  END FUNCTION random
+  REAL(8) FUNCTION random2()
+    block
+      block
+        block
+          CALL RANDOM_NUMBER(random2)
+        end block
+      end block
+    end block
+  END FUNCTION random2
+end module m
+
+! { dg-final { scan-module-absence "m" "IMPLICIT_PURE" } }