From acdbbeee44f9c3cb3c6489bed9f51cbfd9658bcc Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Daniel=20Marjam=C3=A4ki?= <daniel.marjamaki@gmail.com>
Date: Sun, 25 Aug 2013 08:54:33 +0200
Subject: [PATCH] Fixed #4913 (Tokenizer::simplifyKnownVariables: wrong
 handling of *--p=0;)

---
 lib/tokenize.cpp      | 2 +-
 test/testtokenize.cpp | 5 +++++
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/lib/tokenize.cpp b/lib/tokenize.cpp
index b5a1119af..51f49904b 100644
--- a/lib/tokenize.cpp
+++ b/lib/tokenize.cpp
@@ -6170,7 +6170,7 @@ bool Tokenizer::simplifyKnownVariables()
                     break;
             }
 
-            else if (tok2->previous()->str() != "*" &&
+            else if (tok2->previous()->str() != "*" && !Token::Match(tok2->tokAt(-2), "* --|++") &&
                      (Token::Match(tok2, "%var% = %bool%|%char%|%num%|%str%|%var% ;") ||
                       Token::Match(tok2, "%var% [ ] = %str% ;") ||
                       Token::Match(tok2, "%var% [ %num% ] = %str% ;") ||
diff --git a/test/testtokenize.cpp b/test/testtokenize.cpp
index 391eba596..0f1620ae0 100644
--- a/test/testtokenize.cpp
+++ b/test/testtokenize.cpp
@@ -176,6 +176,7 @@ private:
         TEST_CASE(simplifyKnownVariables51);    // #4409 hang
         TEST_CASE(simplifyKnownVariables52);    // #4728 "= x %cop%"
         TEST_CASE(simplifyKnownVariables53);    // references
+        TEST_CASE(simplifyKnownVariables54);    // #4913 'x' is not 0 after *--x=0;
         TEST_CASE(simplifyKnownVariablesIfEq1); // if (a==5) => a is 5 in the block
         TEST_CASE(simplifyKnownVariablesIfEq2); // if (a==5) { buf[a++] = 0; }
         TEST_CASE(simplifyKnownVariablesIfEq3); // #4708 - if (a==5) { buf[--a] = 0; }
@@ -2732,6 +2733,10 @@ private:
         ASSERT_EQUALS("void f ( ) { int * p ; p = abc ( ) ; }", tokenizeAndStringify("void f() { int *p; int *&ref=p; ref=abc(); }", true));
     }
 
+    void simplifyKnownVariables54() { // #4913
+        ASSERT_EQUALS("void f ( int * p ) { * -- p = 0 ; * p = 0 ; }", tokenizeAndStringify("void f(int*p) { *--p=0; *p=0; }", true));
+    }
+
     void simplifyKnownVariablesIfEq1() {
         const char code[] = "void f(int x) {\n"
                             "    if (x==5) {\n"