[compiler-rt] [win/asan] Add a test skeleton for function GetInstructionSize. (PR #116948)

[via llvm-commits]

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@@ -907,6 +912,11 @@ static size_t GetInstructionSize(uptr address, size_t* rel_offset = nullptr) {
   return 0;
 }
 
+// Unfortunately size_t is not known when compiling asan_allocator.cpp
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bernhardu wrote:

Sorry I have replaced just the SIZE_T in the test, unfortunately not yet in interception_win.cpp.
Now the only SIZE_T should be in the header.

https://github.com/llvm/llvm-project/pull/116948