[cfe-commits] r137980 - in /cfe/trunk: include/clang/Basic/Builtins.def include/clang/Basic/DiagnosticSemaKinds.td include/clang/Sema/Sema.h lib/Sema/SemaChecking.cpp test/Sema/warn-strlcpycat-size.c

[Ted Kremenek]

On Aug 18, 2011, at 2:33 PM, Eli Friedman wrote:

>> +// Warn if the user has made the 'size' argument to strlcpy or strlcat
>> +// be the size of the source, instead of the destination.
>> +void Sema::CheckStrlcpycatArguments(const CallExpr *Call,
>> +                                    IdentifierInfo *FnName) {
>> +
>> +  // Don't crash if the user has the wrong number of arguments
>> +  if (Call->getNumArgs() != 3)
>> +    return;
>> +
>> +  const Expr *SrcArg = ignoreLiteralAdditions(Call->getArg(1), Context);
>> +  const Expr *SizeArg = ignoreLiteralAdditions(Call->getArg(2), Context);
>> +  const Expr *CompareWithSrc = NULL;
>> +
>> +  // Look for 'strlcpy(dst, x, sizeof(x))'
>> +  if (const Expr *Ex = getSizeOfExprArg(SizeArg))
>> +    CompareWithSrc = Ex;
>> +  else {
>> +    // Look for 'strlcpy(dst, x, strlen(x))'
>> +    if (const CallExpr *SizeCall = dyn_cast<CallExpr>(SizeArg)) {
>> +      if (SizeCall->isBuiltinCall(Context) == Builtin::BIstrlen
>> +          && SizeCall->getNumArgs() == 1)
>> +        CompareWithSrc = ignoreLiteralAdditions(SizeCall->getArg(0), Context);
>> +    }
>> +  }
> 
> strlcpy(dst, x, strlen(foo)) is clearly wrong no matter what foo is;
> should we warn unconditionally?

Seems reasonable to me.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/cfe-commits/attachments/20110818/c5473258/attachment.html>