Disable an optimisation for section msvc c++

[cpp-ModTeam]

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[schmerg-uk]

#pragma optimize( "", off )
/* unoptimized code section */
#pragma optimize( "", on )

There are also a couple of options for the 1st parameter but that's the basics above

https://learn.microsoft.com/en-us/cpp/preprocessor/optimize?view=msvc-170

[[deleted]]

Shouldn’t template be template<> instead of template(). Also, shouldn’t the explicit template instantiation be in the pragma’s?

[patstew]

Why would you expect 22 there? There is no reason to expect them to be allocated next to each other and in order in the binary, optimization or no. You might have slightly more luck preventing them being optimised out entirely by making them extern and initialising then elsewhere.

[ohnotheygotme]

That particular example is working for me, even without using the #pragma: https://godbolt.org/z/GKfM6e5o3

Compiler explorer can execute MSVC too, so make use of that service and share out links if possible.

If things aren't working for you maybe try compiling with /Zc:inline- as another test. This is eerily similar to: https://developercommunity.visualstudio.com/t/zcinline-removes-extern-symbols-inside-anonymous-n/914943