Qt6: QList<T>operator== requires const T::operator== #116
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This causes a g++ compile error in codemodel.cpp (the error message is extremely confusing). It "works" in Qt5 but adding the "const" in the relevant places does not break the compile. Therefore: bool TypeInfo::operator==(const TypeInfo&) does not modify the LHS; this means that adding the const is safe (there would be a compile error if somoething in the implementation did modify part of the LHS). It makes sense to me that Qt6 would do something to prevent an == operator with a mutable LHS. So far as I can see QList would have to make a complete copy of the LHS under some circumstances resulting in a potentially significant performance hit (depending on the complexity of the type involved). This is a harmless but possibly beneficial change to both 'master' and 'qt6' branches. Signed-off-by: John Bowler <jbowler@acm.org>
mrbean-bremen
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Oct 29, 2023
- missing consta caused a g++ compile error - adding the const is safe, as it does not modify the LHS
mrbean-bremen
pushed a commit
that referenced
this pull request
Oct 29, 2023
- missing consta caused a g++ compile error - adding the const is safe, as it does not modify the LHS
mrbean-bremen
pushed a commit
that referenced
this pull request
Nov 1, 2023
- missing consta caused a g++ compile error - adding the const is safe, as it does not modify the LHS
mrbean-bremen
pushed a commit
that referenced
this pull request
Nov 2, 2023
- missing consta caused a g++ compile error - adding the const is safe, as it does not modify the LHS
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This causes a g++ compile error in codemodel.cpp (the error message is extremely confusing). It "works" in Qt5 but adding the "const" in the relevant places does not break the compile. Therefore:
bool TypeInfo::operator==(const TypeInfo&)
does not modify the LHS; this means that adding the const is safe (there would be a compile error if somoething in the implementation did modify part of the LHS).
It makes sense to me that Qt6 would do something to prevent an == operator with a mutable LHS. So far as I can see QList would have to make a complete copy of the LHS under some circumstances resulting in a potentially significant performance hit (depending on the complexity of the type involved).
This is a harmless but possibly beneficial change to both 'master' and 'qt6' branches.