Fix gcc warnings when building with optimizations. (backport #672) #673
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* Fix gcc warnings when building with optimizations. When building the allocator_tutorial_pmr demo with -O2, gcc is throwing an error saying that new and delete are mismatched. This is something of a misnomer, however; the real problem is that the global new override we have in that demo is actually implemented incorrectly. In particular, the documentation at https://en.cppreference.com/w/cpp/memory/new/operator_new very clearly specifies that operator new either has to return a valid pointer, or throw an exception on error. Our version wasn't throwing the exception, so change it to throw std::bad_alloc if std::malloc fails. While we are in here, also fix another small possible is where std::malloc could return nullptr on a zero-sized object, thus throwing an exception it shouldn't. Signed-off-by: Chris Lalancette <clalancette@gmail.com> * Always inline the new and delete operators. That's because gcc 13 has a bug where it can sometimes inline one or the other, and then it detects that they mismatch. For gcc and clang, just force them to always be inline in this demo. Signed-off-by: Chris Lalancette <clalancette@gmail.com> * Switch to NOINLINE instead. Both clang and MSVC don't like inlining these, so instead ensure that they are *not* inlined. This also works because the problem is when new is inlined but not delete (or vice-versa). As long as they are both not inlined, this should fix the warning. Signed-off-by: Chris Lalancette <clalancette@gmail.com> (cherry picked from commit 957ddbb)
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Apr 29, 2024
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When building the allocator_tutorial_pmr demo with -O2, gcc is throwing an error saying that new and delete are mismatched. This is something of a misnomer, however; the real problem is that the global new override we have in that demo is actually implemented incorrectly.
In particular, the documentation at
https://en.cppreference.com/w/cpp/memory/new/operator_new very clearly specifies that operator new either has to return a valid pointer, or throw an exception on error. Our version wasn't throwing the exception, so change it to throw std::bad_alloc if std::malloc fails.
While we are in here, also fix another small possible is where std::malloc could return nullptr on a zero-sized object, thus throwing an exception it shouldn't.
This is an automatic backport of pull request #672 done by Mergify.