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Issues with Microsoft Visual Studio C++ compiler when compiling Vector Class Library

Vector parameters not aligned

Older versions of MS compiler cannot have vectors as function parameters.
You get error messages like "error C2719: formal parameter with __declspec(align('16')) won't be aligned"
Fixed in later versions

Cannot specify instruction set on command line

Visual Studio version 19 cannot specify instruction sets higher than "/arch:AVX2" on the command line.
It is still possible to code for higher instruction sets by using instrinsic functions, but there is not check that the code matches a particular instruction set.
Version 2022 supports "/arch:AVX512", but not all subsets.

Code compiled for AVX512F includes AVX512DQ instructions

A consequence of the previous issue is that Visual Studio may issue instructions beyond AVX512F when compiling for AVX512F.
Example:

#define INSTRSET 9  // AVX512F
#include "vectorclass.h"
Vec8d test (Vec8d a, Vec8d b) {
    return select (a > b && a < b+1, a, b);
}

Visual Studio version 19 is issuing kmovb instructions when compiling this.
This program will crash on a CPU with AVX512F only, because the kmovb instruction belongs to the AVX512DQ instruction set.
Bug report:
https://developercommunity.visualstudio.com/content/problem/613737/can-i-use-mmask8-in-intrinsic-functions-without-av.html

The reply from Microsoft so far is not assuring (2019-08-04)

Compiler crash on blend8 instruction with Vec8q

Bug report:
https://developercommunity.visualstudio.com/content/problem/676415/vx2019-compiler-crash-on-union-in-constexpr-functi.html
Work-around and future fix, see: https://developercommunity.visualstudio.com/content/problem/676415/vx2019-compiler-crash-on-union-in-constexpr-functi.html?childToView=716149
Fixed