Fix uninitvar miss on ternary (?:) condition - #92
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isVariableUsage() did not treat a variable appearing as the condition of a ternary operator as a read, because '?' is an eExtendedOp token and is therefore rejected by Token::isOp(). The scope analysis then assumed the variable was assigned and stopped, so `x = flag ? 10 : 0;` was silently accepted while `if (flag)` was correctly reported. Fixes Tencent#90
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Summary
uninitvarwas not reported when an uninitialized local variable was used as the condition of a ternary operator, e.g.RetVal = Flag ? 10 : 0;. The same use inif (Flag)was already detected.isVariableUsage()only treated the next token as a use whenToken::isOp()was true.?iseExtendedOp, so it was not recognized as a read; scope analysis then assumed the variable had been assigned and stopped.?(astParent()is?andastOperand1()is the variable), treat it as a use. Added a sample insamples/cpp/uninitvar.cpp.Test plan
make -C trunk(CLI objects needed extra flags on this environment due to existingSIGSTKSZ/intptr_tissues, unrelated to this change)./trunk/tscancode --xml samples/cpp/uninitvar.cppreportsUninitialized variable: flagon the ternary lineUninitialized variable: aona++if (Flag)still reports uninitvar as before