Cleaning up MSVC warnings and syncing with bazel warnings.
diff --git a/build_tools/cmake/iree_copts.cmake b/build_tools/cmake/iree_copts.cmake
index 388282f..ec1f394 100644
--- a/build_tools/cmake/iree_copts.cmake
+++ b/build_tools/cmake/iree_copts.cmake
@@ -185,6 +185,24 @@
# https://docs.microsoft.com/en-us/cpp/c-runtime-library/math-constants
"/D_USE_MATH_DEFINES"
+ # Disable the "deprecation" warnings about CRT functions like strcpy.
+ # Though the secure versions *are* better, they aren't portable and as such
+ # just make cross-platform code annoying. One solution is to reimplement
+ # them in a portable fashion and use those - and that's what we try to do
+ # in certain places where we can get away with it. Other uses, like getenv,
+ # are fine as these are not intended for use in core runtime code that needs
+ # to be secure (friends don't let friends ship entire compiler stacks
+ # embedded inside security sensitive applications anyway :).
+ # https://docs.microsoft.com/en-us/cpp/c-runtime-library/security-features-in-the-crt
+ "/D_CRT_SECURE_NO_WARNINGS"
+
+ # With the above said about the "deprecated" functions; this useful flag
+ # will at least try to use them when possible without any change to user
+ # code. Note however because the new versions use templates they won't be
+ # activated in C code; that's fine.
+ # https://docs.microsoft.com/en-us/cpp/c-runtime-library/secure-template-overloads
+ "/D_CRT_SECURE_CPP_OVERLOAD_STANDARD_NAMES"
+
# Configure exception handling for standard C++ behavior.
# - /EHs enables C++ catch-style exceptions
# - /EHc breaks unwinding across extern C boundaries, dramatically reducing
@@ -204,7 +222,18 @@
# https://docs.microsoft.com/en-us/cpp/build/reference/bigobj-increase-number-of-sections-in-dot-obj-file
"/bigobj"
- "/wd4624"
+ # "nonstandard extension used : zero-sized array in struct/union"
+ # This happens with unsized or zero-length arrays at the end of structs,
+ # which is completely valid in C where we do it and get this warning. Shut
+ # it up and rely on the better warnings from clang to catch if we try to
+ # use it where it really matters (on a class that has copy/move ctors, etc).
+ # https://docs.microsoft.com/en-us/cpp/error-messages/compiler-warnings/compiler-warning-levels-2-and-4-c4200
+ "/wd4200"
+
+ # Misc tweaks to better match clang/gcc behavior:
+ "/wd4065" # switch statement contains 'default' but no 'case' labels
+ "/wd4146" # operator applied to unsigned type, result still unsigned
+
"/wd4141" # duplicate inline attributes
"/wd4005" # macro redefinition
"/wd4267"
