Fix issue 9293: false negative: uninitvar

This commit is contained in:
Paul Fultz II 2019-09-03 06:46:34 +02:00 committed by Daniel Marjamäki
parent dc201d110d
commit 55a78f482b
2 changed files with 41 additions and 12 deletions

View File

@ -1338,28 +1338,31 @@ void CheckUninitVar::valueFlowUninit()
tok = tok->linkAt(1); tok = tok->linkAt(1);
continue; continue;
} }
if (!tok->variable()) if (!tok->variable() && !tok->isUnaryOp("*"))
continue; continue;
auto v = std::find_if(tok->values().begin(), tok->values().end(), std::mem_fn(&ValueFlow::Value::isUninitValue)); auto v = std::find_if(tok->values().begin(), tok->values().end(), std::mem_fn(&ValueFlow::Value::isUninitValue));
if (v == tok->values().end()) if (v == tok->values().end())
continue; continue;
if (v->isInconclusive()) if (v->isInconclusive())
continue; continue;
if (!isVariableUsage(tok, tok->variable()->isPointer(), tok->variable()->isArray() ? ARRAY : NO_ALLOC))
continue;
if (v->indirect > 1 || v->indirect < 0) if (v->indirect > 1 || v->indirect < 0)
continue; continue;
bool uninitderef = false;
if (tok->variable()) {
if (!isVariableUsage(tok, tok->variable()->isPointer(), tok->variable()->isArray() ? ARRAY : NO_ALLOC))
continue;
bool unknown; bool unknown;
const bool deref = CheckNullPointer::isPointerDeRef(tok, unknown, mSettings); const bool deref = CheckNullPointer::isPointerDeRef(tok, unknown, mSettings);
if (v->indirect == 1 && !deref) if (v->indirect == 1 && !deref)
continue; continue;
const bool uninitderef = deref && v->indirect == 0; uninitderef = deref && v->indirect == 0;
const bool isleaf = isLeafDot(tok) || uninitderef; const bool isleaf = isLeafDot(tok) || uninitderef;
if (Token::Match(tok->astParent(), ". %var%") && !isleaf) if (Token::Match(tok->astParent(), ". %var%") && !isleaf)
continue; continue;
}
if (!Token::Match(tok->astParent(), ". %name% (") && !uninitderef && isVariableChanged(tok, v->indirect, mSettings, mTokenizer->isCPP())) if (!Token::Match(tok->astParent(), ". %name% (") && !uninitderef && isVariableChanged(tok, v->indirect, mSettings, mTokenizer->isCPP()))
continue; continue;
uninitvarError(tok, tok->str(), v->errorPath); uninitvarError(tok, tok->expressionString(), v->errorPath);
const Token * nextTok = tok; const Token * nextTok = tok;
while (Token::simpleMatch(nextTok->astParent(), ".")) while (Token::simpleMatch(nextTok->astParent(), "."))
nextTok = nextTok->astParent(); nextTok = nextTok->astParent();

View File

@ -4307,6 +4307,32 @@ private:
"}\n"); "}\n");
ASSERT_EQUALS("[test.cpp:8]: (error) Uninitialized variable: pcdata\n", errout.str()); ASSERT_EQUALS("[test.cpp:8]: (error) Uninitialized variable: pcdata\n", errout.str());
// # 9293
valueFlowUninit("struct S {\n"
" int x;\n"
" int y;\n"
"};\n"
"\n"
"void f() {\n"
" struct S s1;\n"
" int * x = &s1.x;\n"
" struct S s2 = {*x, 0}; \n"
"}\n");
ASSERT_EQUALS("[test.cpp:8] -> [test.cpp:9]: (error) Uninitialized variable: *x\n", errout.str());
valueFlowUninit("struct S {\n"
" int x;\n"
" int y;\n"
"};\n"
"\n"
"void f() {\n"
" struct S s1;\n"
" struct S s2;\n"
" int * x = &s1.x;\n"
" s2.x = *x; \n"
"}\n");
ASSERT_EQUALS("[test.cpp:9] -> [test.cpp:10]: (error) Uninitialized variable: *x\n", errout.str());
valueFlowUninit("void f(bool * x) {\n" valueFlowUninit("void f(bool * x) {\n"
" *x = false;\n" " *x = false;\n"
"}\n" "}\n"