r318456 - Issue -Wempty-body warnings for else blocks

[Reid Kleckner via cfe-commits]

Author: rnk
Date: Thu Nov 16 13:26:18 2017
New Revision: 318456

URL: http://llvm.org/viewvc/llvm-project?rev=318456&view=rev
Log:
Issue -Wempty-body warnings for else blocks

This looks like it was just an oversight.

Fixes http://llvm.org/pr35319

Modified:
    cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td
    cfe/trunk/lib/Sema/SemaStmt.cpp
    cfe/trunk/test/SemaCXX/warn-empty-body.cpp

Modified: cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td?rev=318456&r1=318455&r2=318456&view=diff
==============================================================================
--- cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td (original)
+++ cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td Thu Nov 16 13:26:18 2017
@@ -8090,6 +8090,8 @@ def err_switch_incomplete_class_type : E
 
 def warn_empty_if_body : Warning<
   "if statement has empty body">, InGroup<EmptyBody>;
+def warn_empty_else_body : Warning<
+  "else clause has empty body">, InGroup<EmptyBody>;
 def warn_empty_for_body : Warning<
   "for loop has empty body">, InGroup<EmptyBody>;
 def warn_empty_range_based_for_body : Warning<

Modified: cfe/trunk/lib/Sema/SemaStmt.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaStmt.cpp?rev=318456&r1=318455&r2=318456&view=diff
==============================================================================
--- cfe/trunk/lib/Sema/SemaStmt.cpp (original)
+++ cfe/trunk/lib/Sema/SemaStmt.cpp Thu Nov 16 13:26:18 2017
@@ -527,7 +527,9 @@ Sema::ActOnIfStmt(SourceLocation IfLoc,
                        CondExpr->getExprLoc()))
     CommaVisitor(*this).Visit(CondExpr);
 
-  if (!elseStmt)
+  if (elseStmt)
+    DiagnoseEmptyStmtBody(ElseLoc, elseStmt, diag::warn_empty_else_body);
+  else
     DiagnoseEmptyStmtBody(CondExpr->getLocEnd(), thenStmt,
                           diag::warn_empty_if_body);
 

Modified: cfe/trunk/test/SemaCXX/warn-empty-body.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaCXX/warn-empty-body.cpp?rev=318456&r1=318455&r2=318456&view=diff
==============================================================================
--- cfe/trunk/test/SemaCXX/warn-empty-body.cpp (original)
+++ cfe/trunk/test/SemaCXX/warn-empty-body.cpp Thu Nov 16 13:26:18 2017
@@ -238,6 +238,26 @@ void test6(int x, int y) {
   }
 }
 
+void test_if_else(int x) {
+  if (x); // expected-warning{{if statement has empty body}} expected-note{{separate line}}
+
+  if (x)
+    ; // no-warning
+
+  if (x)
+    ; // no-warning
+  else
+    ; // no-warning
+
+  if (x)
+    ; // no-warning
+  else; // expected-warning{{else clause has empty body}} expected-note{{separate line}}
+
+  if (x)
+    ; // no-warning
+  else EMPTY(x); // no-warning
+}
+
 void test_errors(int x) {
   if (1)
     aa; // expected-error{{use of undeclared identifier}}