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Fixed #10448 (FN compareValueOutOfTypeRangeError with int32_t)

This commit is contained in:
Daniel Marjamäki 2021-09-12 15:08:14 +02:00
parent 8de160a163
commit b455f847ba
3 changed files with 41 additions and 13 deletions
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39
lib/checkcondition.cpp
View File

@ -1809,26 +1809,49 @@ void CheckCondition::checkCompareValueOutOfTypeRange()
const auto typeMinValue = (typeTok->valueType()->sign == ValueType::Sign::UNSIGNED) ? 0 : (-(1LL << (bits-1)));
const auto unsignedTypeMaxValue = (1LL << bits) - 1LL;
const auto typeMaxValue = (typeTok->valueType()->sign != ValueType::Sign::SIGNED || bits >= mSettings->int_bit) ?
unsignedTypeMaxValue : // unsigned type. signed int/long/long long; comparing sign bit is ok. i.e. 'i == 0xffffffff'
(unsignedTypeMaxValue / 2); // signed char/short
long long typeMaxValue;
if (typeTok->valueType()->sign != ValueType::Sign::SIGNED)
typeMaxValue = unsignedTypeMaxValue;
else if (bits >= mSettings->int_bit && valueTok->valueType()->sign != ValueType::Sign::SIGNED)
typeMaxValue = unsignedTypeMaxValue;
else
typeMaxValue = unsignedTypeMaxValue / 2;
if (valueTok->getKnownIntValue() < typeMinValue)
compareValueOutOfTypeRangeError(valueTok, typeTok->valueType()->str(), valueTok->getKnownIntValue());
bool result;
if (tok->str() == "==")
result = false;
else if (tok->str() == "!=")
result = true;
else if (tok->str()[0] == '>' && i == 0)
// num > var
result = (valueTok->getKnownIntValue() > 0);
else if (tok->str()[0] == '>' && i == 1)
// var > num
result = (valueTok->getKnownIntValue() < 0);
else if (tok->str()[0] == '<' && i == 0)
// num < var
result = (valueTok->getKnownIntValue() < 0);
else if (tok->str()[0] == '<' && i == 1)
// var < num
result = (valueTok->getKnownIntValue() > 0);
if (valueTok->getKnownIntValue() < typeMinValue) {
compareValueOutOfTypeRangeError(valueTok, typeTok->valueType()->str(), valueTok->getKnownIntValue(), result);
}
else if (valueTok->getKnownIntValue() > typeMaxValue)
compareValueOutOfTypeRangeError(valueTok, typeTok->valueType()->str(), valueTok->getKnownIntValue());
compareValueOutOfTypeRangeError(valueTok, typeTok->valueType()->str(), valueTok->getKnownIntValue(), result);
}
}
}
}
void CheckCondition::compareValueOutOfTypeRangeError(const Token *comparison, const std::string &type, long long value)
void CheckCondition::compareValueOutOfTypeRangeError(const Token *comparison, const std::string &type, long long value, bool result)
{
reportError(
comparison,
Severity::style,
"compareValueOutOfTypeRangeError",
"Comparing expression of type '" + type + "' against value " + std::to_string(value) + ". Condition is always true/false.",
"Comparing expression of type '" + type + "' against value " + std::to_string(value) + ". Condition is always " + (result ? "true" : "false") + ".",
CWE398,
Certainty::normal);
}

4
lib/checkcondition.h
View File

@ -167,7 +167,7 @@ private:
void assignmentInCondition(const Token *eq);
void checkCompareValueOutOfTypeRange();
void compareValueOutOfTypeRangeError(const Token *comparison, const std::string &type, long long value);
void compareValueOutOfTypeRangeError(const Token *comparison, const std::string &type, long long value, bool result);
void getErrorMessages(ErrorLogger *errorLogger, const Settings *settings) const OVERRIDE {
CheckCondition c(nullptr, settings, errorLogger);
@ -192,7 +192,7 @@ private:
c.pointerAdditionResultNotNullError(nullptr, nullptr);
c.duplicateConditionalAssignError(nullptr, nullptr);
c.assignmentInCondition(nullptr);
c.compareValueOutOfTypeRangeError(nullptr, "unsigned char", 256);
c.compareValueOutOfTypeRangeError(nullptr, "unsigned char", 256, true);
}
static std::string myName() {

11
test/testcondition.cpp
View File

@ -4586,7 +4586,7 @@ private:
check("void f(unsigned char c) {\n"
" if (c == 256) {}\n"
"}", &settingsUnix64);
ASSERT_EQUALS("[test.cpp:2]: (style) Comparing expression of type 'unsigned char' against value 256. Condition is always true/false.\n", errout.str());
ASSERT_EQUALS("[test.cpp:2]: (style) Comparing expression of type 'unsigned char' against value 256. Condition is always false.\n", errout.str());
check("void f(unsigned char c) {\n"
" if (c == 255) {}\n"
@ -4602,12 +4602,12 @@ private:
check("void f(signed char x) {\n"
" if (x == 0xff) {}\n"
"}", &settingsUnix64);
ASSERT_EQUALS("[test.cpp:2]: (style) Comparing expression of type 'signed char' against value 255. Condition is always true/false.\n", errout.str());
ASSERT_EQUALS("[test.cpp:2]: (style) Comparing expression of type 'signed char' against value 255. Condition is always false.\n", errout.str());
check("void f(short x) {\n"
" if (x == 0xffff) {}\n"
"}", &settingsUnix64);
ASSERT_EQUALS("[test.cpp:2]: (style) Comparing expression of type 'signed short' against value 65535. Condition is always true/false.\n", errout.str());
ASSERT_EQUALS("[test.cpp:2]: (style) Comparing expression of type 'signed short' against value 65535. Condition is always false.\n", errout.str());
check("void f(int x) {\n"
" if (x == 0xffffffff) {}\n"
@ -4629,6 +4629,11 @@ private:
" if ((c = foo()) != -1) {}\n"
"}", &settingsUnix64);
ASSERT_EQUALS("", errout.str());
check("void f(int x) {\n"
" if (x < 3000000000) {}\n"
"}", &settingsUnix64);
ASSERT_EQUALS("[test.cpp:2]: (style) Comparing expression of type 'signed int' against value 3000000000. Condition is always true.\n", errout.str());
}
void knownConditionCast() { // #9976