Fixed #8054 (Tokenizer::simplifyKnownVariables(): Wrong simplification for global variables)

lib/tokenize.cpp

@@ -6242,7 +6242,8 @@ bool Tokenizer::simplifyKnownVariables()
         }
     }
 
-    // variable id for float/double variables
+    // variable id for local, float/double, array variables
+    std::set<unsigned int> localvars;
     std::set<unsigned int> floatvars;
     std::set<unsigned int> arrays;
 
@@ -6253,20 +6254,33 @@ bool Tokenizer::simplifyKnownVariables()
         if (!start)
             continue;
 
+        for (const Token *tok2 = start->previous(); tok2 && !Token::Match(tok2, "[;{}]"); tok2 = tok2->previous()) {
+            if (tok2->varId() != 0)
+                localvars.insert(tok2->varId());
+        }
+
         tok = start;
         // parse the block of code..
         int indentlevel = 0;
         Token *tok2 = tok;
         for (; tok2; tok2 = tok2->next()) {
-            if (Token::Match(tok2, "[;{}] float|double %name% ;")) {
-                floatvars.insert(tok2->tokAt(2)->varId());
+            if (Token::Match(tok2, "[;{}] %type% %name%|*")) {
+                bool isfloat = false;
+                bool ispointer = false;
+                const Token *vartok = tok2->next();
+                while (Token::Match(vartok, "%name%|* %name%|*")) {
+                    if (Token::Match(vartok, "float|double"))
+                        isfloat = true;
+                    if (vartok->str() == "*")
+                        ispointer = true;
+                    vartok = vartok->next();
                 }
-
-            if (Token::Match(tok2, "[;{}] %type% *| %name% [")) {
-                const Token *nameToken = tok2->tokAt(2);
-                if (nameToken->str() == "*")
-                    nameToken = nameToken->next();
-                arrays.insert(nameToken->varId());
+                if (Token::Match(vartok, "%var% ;|["))
+                    localvars.insert(vartok->varId());
+                if (isfloat && !ispointer && Token::Match(vartok, "%var% ;"))
+                    floatvars.insert(vartok->varId());
+                if (Token::Match(vartok, "%var% ["))
+                    arrays.insert(vartok->varId());
             }
 
             if (tok2->str() == "{")
@@ -6290,6 +6304,9 @@ bool Tokenizer::simplifyKnownVariables()
                 if (varid == 0)
                     continue;
 
+                if (Token::Match(tok2->previous(), "[;{}]") && localvars.find(varid) == localvars.end())
+                    continue;
+
                 // initialization of static variable => the value is not *known*
                 {
                     bool isstatic = false;

test/testtokenize.cpp

@@ -203,6 +203,7 @@ private:
         TEST_CASE(simplifyKnownVariablesFloat);    // #2454 - float variable
         TEST_CASE(simplifyKnownVariablesClassMember);  // #2815 - value of class member may be changed by function call
         TEST_CASE(simplifyKnownVariablesFunctionCalls); // Function calls (don't assume pass by reference)
+        TEST_CASE(simplifyKnownVariablesGlobalVars);
         TEST_CASE(simplifyKnownVariablesReturn);   // 3500 - return
         TEST_CASE(simplifyKnownVariablesPointerAliasFunctionCall); // #7440
         TEST_CASE(simplifyExternC);
@@ -2949,6 +2950,16 @@ private:
         }
     }
 
+    void simplifyKnownVariablesGlobalVars() {
+        // #8054
+        const char code[] = "static int x;"
+                            "void f() {"
+                            "    x = 123;"
+                            "    while (!x) { dostuff(); }"
+                            "}";
+        ASSERT_EQUALS("static int x ; void f ( ) { x = 123 ; while ( ! x ) { dostuff ( ) ; } }", tokenizeAndStringify(code,true));
+    }
+
     void simplifyKnownVariablesReturn() {
         const char code[] = "int a() {"
                             "    int x = 123;"