[cfe-dev] Question on static analyzer callback: checkBranchCondition()

[illiop via cfe-dev]

Hello,
Thanks in advance for any help!
 
If I have the following code:
 
void function()
{
       int a = 1;
       if ( ( a<10 ) && ( a > 20 ) ) // always false
      {
      } 
}
 
How can I evaluate the whole condition expression  '( a<10 ) && ( a > 20 ) ' ?
When I write code like:
class MyChecker : public Checker< check::BranchCOndition >
{  
public:
   void checkBranchCondition(const Stmt* cond, CheckerContext& ctx) const;
}
 
I found that checkBranchCondition() only be called back 2 times, once for 'a<10' , once for 'a > 20 '.  And it's done. No further call back.
But my goal is to get the 'value' for the whole  '( a<10 ) && ( a > 20 ) '.
I tried the following in vain:
 
1. in checkBranchCondition(), find the 'father' node(it is '( a<10 ) && ( a > 20 ) ' ), and evaluate its 'sval', but the sval is invalid/undifined
2. Use check::PostStmt<CompoundStmt> call back. It does NOT called back at all
3. Use check::PostStmt<Stmt> call back, and try to find the 'father' by : if(isa<IfStmt>(stmt)), useless.
4. Use check::PostStmt<BinaryOperator>, but it still only called back 2 times:  once for 'a<10' , once for 'a > 20 '
 
I am a fresh man in the static analyzer, please help, thanks!
 
illiop
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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