Merge pull request gcc-mirror#73 from NinaRanns/contracts_disable_warnings

disabling warning for parameters of contract check and contract wrapp…

Author: villevoutilainen

gcc/cp/contracts.cc

@@ -1554,6 +1554,11 @@ build_contract_condition_function (tree fndecl, bool pre)
   /* The handlers are void fns.  */
   TREE_TYPE (fn) = build_function_type (void_type_node, arg_types);
 
+  /* Disable warnings for all the parameters */
+  for (tree p = DECL_ARGUMENTS (fn); p && p!=void_list_node;
+      p = TREE_CHAIN (p))
+    suppress_warning (p);
+
   if (DECL_IOBJ_MEMBER_FUNCTION_P (fndecl))
     TREE_TYPE (fn) = build_method_type (class_type, TREE_TYPE (fn));
 
@@ -1591,7 +1596,7 @@ build_contract_condition_function (tree fndecl, bool pre)
   /* Update various inline related declaration properties.  */
   //DECL_DECLARED_INLINE_P (fn) = true;
   DECL_DISREGARD_INLINE_LIMITS (fn) = true;
-  TREE_NO_WARNING (fn) = true;
+  suppress_warning (fn);
 
   return fn;
 }
@@ -1932,6 +1937,7 @@ build_contract_wrapper_function (tree fndecl, bool is_cvh,
 	TREE_CHAIN (last) = void_list_node;
 	break;
       }
+      suppress_warning (p);
       last = TREE_CHAIN (last) = copy_decl (p);
       DECL_CONTEXT (last) = wrapdecl;
     }
@@ -1962,7 +1968,7 @@ build_contract_wrapper_function (tree fndecl, bool is_cvh,
   /* Update various inline related declaration properties.  */
   //DECL_DECLARED_INLINE_P (wrapdecl) = true;
   DECL_DISREGARD_INLINE_LIMITS (wrapdecl) = true;
-  TREE_NO_WARNING (wrapdecl) = true;
+  suppress_warning (wrapdecl);
 
   return wrapdecl;
 }

gcc/testsuite/g++.dg/contracts/cpp26/unused_warning.C

@@ -0,0 +1,25 @@
+// check that we do not get unused warnings for contract check function parameters
+// { dg-do compile }
+// { dg-options "-std=c++2b -fcontracts -fcontracts-nonattr -fcontract-evaluation-semantic=enforce  -Wall -Wextra" }
+
+struct TimeInterval{
+  int i = 4;
+  void addInterval(int i, int j);
+};
+
+TimeInterval operator-(const TimeInterval& lhs, const TimeInterval& rhs)
+    pre(2 != rhs.i);
+
+inline
+TimeInterval operator-(const TimeInterval& lhs,
+                                   const TimeInterval& rhs)
+
+{
+    TimeInterval result(lhs);
+    result.addInterval(-rhs.i, -rhs.i);
+    return result;
+}
+
+int main(int, char**) {
+
+}