walkero
/
cppcheck
1
0
Fork 0
Code Issues Pull Requests Projects Releases 1 Wiki Activity

CheckBool::checkComparisonOfBoolExpressionWithInt: Rewrite the check using AST instead of token list

This commit is contained in:
Daniel Marjamäki 2014-03-27 16:10:43 +01:00
parent 9b307cf8e0
commit 581886636d
2 changed files with 36 additions and 118 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

138
lib/checkbool.cpp
View File

@ -31,7 +31,7 @@ namespace {
static bool astIsBool(const Token *expr) static bool astIsBool(const Token *expr)
{ {
return Token::Match(expr, "%comp%|%bool%|%oror%|&&"); return Token::Match(expr, "%comp%|%bool%|%oror%|&&|!");
} }
//--------------------------------------------------------------------------- //---------------------------------------------------------------------------
@ -357,37 +357,6 @@ void CheckBool::assignBoolToPointerError(const Token *tok)
"Boolean value assigned to pointer."); "Boolean value assigned to pointer.");
} }
/**
* @brief Is the result of the LHS expression non-bool?
* @param tok last token in lhs
* @return true => lhs result is non-bool. false => lhs result type is unknown or bool
*/
static bool isNonBoolLHSExpr(const Token *tok)
{
// return value. only return true if we "know" it's a non-bool expression
bool nonBoolExpr = false;
for (; tok; tok = tok->previous()) {
if (tok->str() == ")") {
if (!Token::Match(tok->link()->previous(), "&&|%oror%|( ("))
tok = tok->link();
} else if (tok->str() == "(" || tok->str() == "[")
break;
else if (tok->isNumber())
nonBoolExpr = true;
else if (tok->isArithmeticalOp()) {
return true;
} else if (tok->isComparisonOp() || (tok->str() == "!" && tok->previous()->str()=="("))
return false;
else if (Token::Match(tok,"[;{}=?:&|^,]"))
break;
else if (Token::Match(tok, "&&|%oror%|and|or"))
break;
}
return nonBoolExpr;
}
//----------------------------------------------------------------------------- //-----------------------------------------------------------------------------
//----------------------------------------------------------------------------- //-----------------------------------------------------------------------------
void CheckBool::checkComparisonOfBoolExpressionWithInt() void CheckBool::checkComparisonOfBoolExpressionWithInt()
@ -401,6 +370,9 @@ void CheckBool::checkComparisonOfBoolExpressionWithInt()
for (std::size_t i = 0; i < functions; ++i) { for (std::size_t i = 0; i < functions; ++i) {
const Scope * scope = symbolDatabase->functionScopes[i]; const Scope * scope = symbolDatabase->functionScopes[i];
for (const Token* tok = scope->classStart->next(); tok != scope->classEnd; tok = tok->next()) { for (const Token* tok = scope->classStart->next(); tok != scope->classEnd; tok = tok->next()) {
if (!tok->isComparisonOp())
continue;
// Skip template parameters // Skip template parameters
if (tok->str() == "<" && tok->link()) { if (tok->str() == "<" && tok->link()) {
tok = tok->link(); tok = tok->link();
@ -408,97 +380,43 @@ void CheckBool::checkComparisonOfBoolExpressionWithInt()
} }
const Token* numTok = 0; const Token* numTok = 0;
const Token* opTok = 0; const Token* boolExpr = 0;
char op = 0; bool numInRhs;
if (Token::Match(tok, "&&|%oror% %any% ) %comp% %any%")) { if (astIsBool(tok->astOperand1())) {
numTok = tok->tokAt(4); boolExpr = tok->astOperand1();
opTok = tok->tokAt(3); numTok = tok->astOperand2();
if (Token::Match(opTok, "<|>")) numInRhs = true;
op = opTok->str()[0]; } else if (astIsBool(tok->astOperand2())) {
} else if (Token::Match(tok, "%any% %comp% ( %any% &&|%oror%")) { boolExpr = tok->astOperand2();
numTok = tok; numTok = tok->astOperand1();
opTok = tok->next(); numInRhs = false;
if (Token::Match(opTok, "<|>")) } else {
op = opTok->str()[0]=='>'?'<':'>'; continue;
} }
else if (Token::Match(tok, "! %var% %comp% %any%") && !isNonBoolLHSExpr(tok)) { if (Token::Match(boolExpr,"%bool%"))
numTok = tok->tokAt(3); // The CheckBool::checkComparisonOfBoolWithInt warns about this.
opTok = tok->tokAt(2); continue;
if (Token::Match(opTok, "<|>"))
op = opTok->str()[0];
} else if (Token::Match(tok->previous(), "(|&&|%oror% %num% %comp% !")) {
const Token *rhs = tok->tokAt(3);
while (rhs) {
if (rhs->str() == "!") {
if (Token::simpleMatch(rhs, "! ("))
rhs = rhs->next()->link();
rhs = rhs->next();
} else if (rhs->isName() || rhs->isNumber())
rhs = rhs->next();
else
break;
}
if (Token::Match(rhs, "&&|%oror%|)")) {
numTok = tok;
opTok = tok->next();
if (Token::Match(opTok, "<|>"))
op = opTok->str()[0]=='>'?'<':'>';
}
}
// boolean result in lhs compared with <|<=|>|>= if (!numTok || !boolExpr)
else if (tok->isComparisonOp() && !Token::Match(tok,"==|!=") && !isNonBoolLHSExpr(tok->previous())) {
const Token *lhs = tok;
while (nullptr != (lhs = lhs->previous())) {
if ((lhs->isName() && !Token::Match(lhs,"or|and")) || lhs->isNumber())
continue; continue;
if (lhs->isArithmeticalOp())
continue;
if (Token::Match(lhs, ")|]")) {
if (Token::Match(lhs->link()->previous(), "%var% ("))
lhs = lhs->link();
continue;
}
break;
}
if (lhs && (lhs->isComparisonOp() || lhs->str() == "!")) {
if (_tokenizer->isCPP() && tok->str() == ">" &&
(Token::Match(lhs->previous(), "%var% <") || lhs->str() == ">"))
continue;
while (nullptr != (lhs = lhs->previous())) {
if ((lhs->isName() && lhs->str() != "return") || lhs->isNumber())
continue;
if (Token::Match(lhs,"[+-*/.]"))
continue;
if (Token::Match(lhs, ")|]")) {
lhs = lhs->previous();
continue;
}
break;
}
std::string expression; if (boolExpr->isOp() && numTok->isName() && Token::Match(tok, "==|!="))
for (const Token *t = lhs ? lhs->next() : _tokenizer->tokens(); t != tok; t = t->next()) { // there is weird code such as: ((a<b)==c)
if (!expression.empty()) // but it is probably written this way by design.
expression += ' '; continue;
expression += t->str();
}
comparisonOfBoolWithInvalidComparator(tok, expression);
}
}
if (numTok && opTok) {
if (numTok->isNumber()) { if (numTok->isNumber()) {
if (((numTok->str() != "0" && numTok->str() != "1") || !Token::Match(opTok, "!=|==")) && !((op == '<' && numTok->str() == "1") || (op == '>' && numTok->str() == "0"))) if (numTok->str() == "0" && Token::Match(tok, numInRhs ? ">|==|!=" : "<|==|!="))
continue;
if (numTok->str() == "1" && Token::Match(tok, numInRhs ? "<|==|!=" : ">|==|!="))
continue;
comparisonOfBoolExpressionWithIntError(tok, true); comparisonOfBoolExpressionWithIntError(tok, true);
} else if (isNonBoolStdType(numTok->variable())) } else if (isNonBoolStdType(numTok->variable()))
comparisonOfBoolExpressionWithIntError(tok, false); comparisonOfBoolExpressionWithIntError(tok, false);
} }
} }
} }
}
void CheckBool::comparisonOfBoolExpressionWithIntError(const Token *tok, bool n0o1) void CheckBool::comparisonOfBoolExpressionWithIntError(const Token *tok, bool n0o1)
{ {

6
test/testbool.cpp
View File

@ -423,7 +423,7 @@ private:
ASSERT_EQUALS("",errout.str()); ASSERT_EQUALS("",errout.str());
check("void f(int a, int b, int c) { if (1 < !(a+b)) {} }"); check("void f(int a, int b, int c) { if (1 < !(a+b)) {} }");
TODO_ASSERT_EQUALS("error","",errout.str()); ASSERT_EQUALS("[test.cpp:1]: (warning) Comparison of a boolean expression with an integer other than 0 or 1.\n",errout.str());
} }
void comparisonOfBoolExpressionWithInt3() { void comparisonOfBoolExpressionWithInt3() {
@ -438,12 +438,12 @@ private:
check("void f() {\n" check("void f() {\n"
" for(int i = 4; i > -1 < 5 ; --i) {}\n" " for(int i = 4; i > -1 < 5 ; --i) {}\n"
"}"); "}");
ASSERT_EQUALS("[test.cpp:2]: (warning) Comparison of a boolean value using relational operator (<, >, <= or >=).\n", errout.str()); ASSERT_EQUALS("[test.cpp:2]: (warning) Comparison of a boolean expression with an integer other than 0 or 1.\n", errout.str());
check("void f(int a, int b, int c) {\n" check("void f(int a, int b, int c) {\n"
" return (a > b) < c;\n" " return (a > b) < c;\n"
"}"); "}");
TODO_ASSERT_EQUALS("error", "", errout.str()); ASSERT_EQUALS("[test.cpp:2]: (warning) Comparison of a boolean expression with an integer.\n", errout.str());
check("void f(int a, int b, int c) {\n" check("void f(int a, int b, int c) {\n"
" return x(a > b) < c;\n" " return x(a > b) < c;\n"