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V770. Possible use of left shift operator instead of comparison operator.
The analyzer detected a potential typo that deals with using operators '<<' and '<<=' instead of '<' and '<=', respectively, in a loop condition.
Consider the following example:
void Foo(std::vector<int> vec)
{
for (size_t i = 0; i << vec.size(); i++) // <=
{
// Something
}
}The "i << vec.size()" expression evaluates to zero, which is obviously an error because the loop body will not execute even once. Fixed code:
void Foo(std::vector<int> vec)
{
for (size_t i = 0; i < vec.size(); i++)
{
// Something
}
}Note. Using right-shift operations (>>, >>=) is considered a normal situation, as they are used in various algorithms, for example computing the number of bits with the value 1, for example:
size_t num;
unsigned short var = N;
for (num = var & 1 ; var >>= 1; num += var & 1);This diagnostic is classified as:
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