Fixed #844 (Tokenizer: Simplify 'sizeof *ptr' correctly)

danmar · Oct 21, 2009 · b80a954 · b80a954
1 parent eeb281d
commit b80a954
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Showing 2 changed files with 36 additions and 11 deletions.
diff --git a/src/tokenize.cpp b/src/tokenize.cpp
@@ -1585,16 +1585,24 @@ void Tokenizer::simplifySizeof()
         else if (Token::Match(tok, "sizeof ( * %var% )") || Token::Match(tok, "sizeof ( %var% [ %num% ] )"))
         {
             // Some default value..
-            unsigned int sz = 100;
+            unsigned int sz = 0;
 
             unsigned int varid = tok->tokAt((tok->tokAt(2)->str() == "*") ? 3 : 2)->varId();
             if (varid != 0)
             {
                 // Try to locate variable declaration..
-                const Token *decltok = Token::findmatch(_tokens, "%type% %varid% [", varid);
-                if (decltok)
+                const Token *decltok = Token::findmatch(_tokens, "%varid%", varid);
+                if (Token::findmatch(decltok->previous(), "%type% %var% ["))
                 {
-                    sz = sizeOfType(decltok);
+                    sz = sizeOfType(decltok->previous());
+                }
+                else if (Token::findmatch(decltok->previous(), "* %var% ["))
+                {
+                    sz = sizeOfType(decltok->previous());
+                }
+                else if (Token::findmatch(decltok->tokAt(-2), "%type% * %var%"))
+                {
+                    sz = sizeOfType(decltok->tokAt(-2));
                 }
             }
 

diff --git a/test/testsimplifytokens.cpp b/test/testsimplifytokens.cpp
@@ -67,6 +67,7 @@ class TestSimplifyTokens : public TestFixture
         TEST_CASE(sizeof9);
         TEST_CASE(sizeof10);
         TEST_CASE(sizeof11);
+        TEST_CASE(sizeof12);
         TEST_CASE(casting);
 
         TEST_CASE(template1);
@@ -549,11 +550,8 @@ class TestSimplifyTokens : public TestFixture
 
     void sizeof1()
     {
-        const char code1[] = " struct ABC *abc = malloc(sizeof(*abc)); ";
-        const char code2[] = " struct ABC *abc = malloc(100); ";
-        const char code3[] = " struct ABC *abc = malloc(sizeof *abc ); ";
-        ASSERT_EQUALS(tok(code1), tok(code2));
-        ASSERT_EQUALS(tok(code2), tok(code3));
+        ASSERT_EQUALS("struct ABC * abc ; abc = malloc ( 100 ) ;", tok("struct ABC *abc = malloc(sizeof(*abc));"));
+        ASSERT_EQUALS("struct ABC * abc ; abc = malloc ( 100 ) ;", tok("struct ABC *abc = malloc(sizeof *abc );"));
     }
 
 
@@ -597,9 +595,10 @@ class TestSimplifyTokens : public TestFixture
     void sizeof5()
     {
         const char code[] =
-            "for (int i = 0; i < sizeof(g_ReservedNames[0]); i++)"
+            "const char * names[2];"
+            "for (int i = 0; i < sizeof(names[0]); i++)"
             "{}";
-        ASSERT_EQUALS("for ( int i = 0 ; i < 100 ; i ++ ) { }", sizeof_(code));
+        ASSERT_EQUALS("const char * names [ 2 ] ; for ( int i = 0 ; i < 4 ; i ++ ) { }", sizeof_(code));
     }
 
     void sizeof6()
@@ -821,6 +820,24 @@ class TestSimplifyTokens : public TestFixture
         ASSERT_EQUALS(expected, tok(code));
     }
 
+    void sizeof12()
+    {
+        // ticket #827
+        const char code[] = "void f()\n"
+                            "{\n"
+                            "    int *p;\n"
+                            "    (sizeof *p);\n"
+                            "}";
+
+        const char expected[] = "void f ( ) "
+                                "{"
+                                " int * p ;"
+                                " 4 ; "
+                                "}";
+
+        ASSERT_EQUALS(expected, tok(code));
+    }
+
     void casting()
     {
         {