Fixed #718 (False positive, resource leak when break in a loop before exit)

src/checkmemoryleak.cpp

@@ -1152,6 +1152,14 @@ void CheckMemoryLeakInFunction::simplifycode(Token *tok, bool &all)
                     done = false;
                 }
 
+                // Reduce "if X ; else X ;" => "X ;"
+                else if (Token::Match(tok2->next(), "if %var% ; else %var% ;") &&
+                         std::string(tok2->strAt(2)) == std::string(tok2->strAt(5)))
+                {
+                    Token::eraseTokens(tok2, tok2->tokAt(5));
+                    done = false;
+                }
+
                 // Two "if alloc ;" after one another.. perhaps only one of them can be executed each time
                 else if (!_settings->_showAll && Token::Match(tok2, "[;{}] if alloc ; if alloc ;"))
                 {
@@ -1373,6 +1381,13 @@ void CheckMemoryLeakInFunction::simplifycode(Token *tok, bool &all)
                 done = false;
             }
 
+            // Reduce "loop break ; => ";"
+            if (Token::Match(tok2->next(), "loop break|continue ;"))
+            {
+                Token::eraseTokens(tok2, tok2->tokAt(3));
+                done = false;
+            }
+
             // Reduce "loop if break ; => ";"
             if (Token::Match(tok2->next(), "loop if break|continue ; !!else"))
             {

test/testmemleak.cpp

@@ -460,11 +460,10 @@ private:
         ASSERT_EQUALS("; alloc ; dealloc ;", simplifycode("; alloc; if(!var) { return; } dealloc;"));
         ASSERT_EQUALS("; alloc ;", simplifycode("; if { alloc; } else { return; }"));
         ASSERT_EQUALS("; alloc ; dealloc ;", simplifycode("; alloc ; if(!var) { alloc ; } dealloc ;"));
-
         ASSERT_EQUALS("; use ;", simplifycode("; if(var) use ;"));
+        ASSERT_EQUALS("; break ;", simplifycode("; if break ; else break ;"));
 
         ASSERT_EQUALS("; alloc ; dealloc ;\n; alloc ;", simplifycode("; alloc ; if(!var) { return ; } if { dealloc ; }"));
-
         ASSERT_EQUALS("; if alloc ; else assign ; return use ;", simplifycode("; callfunc ; if callfunc { alloc ; } else { assign ; } return use ;"));
 
         // "if ; .."
@@ -480,6 +479,7 @@ private:
         ASSERT_EQUALS("; alloc ; dealloc ;", simplifycode(";alloc;switch{case;break;};dealloc;"));
 
         // loops..
+        ASSERT_EQUALS(";", simplifycode("; loop { break; }"));
         ASSERT_EQUALS(";", simplifycode("; loop { if { break; } }"));
         ASSERT_EQUALS("; loop alloc ;", simplifycode("; loop { alloc ; }"));
         ASSERT_EQUALS("; alloc ; alloc ;", simplifycode("; alloc ; do { alloc ; } loop ;"));