Mono - Add error on warnings

[AaronRobinsonMSFT]

Contributes to #66154

/cc @lambdageek @vargaz @lateralusX

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Issue Details

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Contributes to #66154

/cc @lambdageek @vargaz @lateralusX

Author:	AaronRobinsonMSFT
Assignees:	-
Labels:	area-Infrastructure-mono
Milestone:	7.0.0

[lambdageek]

/azp run runtime-extra-platforms

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).

[AaronRobinsonMSFT]

@lambdageek Yay for green!

[lambdageek]

@lateralusX we should really build with clang with -Wshorten-64-to-32 so that folks on OSX can get similar warnings that the Windows builds now enforce. Otherwise warnings-as-errors-on-Windows is going to lead to a lot of frustration.

[lateralusX]

@lateralusX we should really build with clang with -Wshorten-64-to-32 so that folks on OSX can get similar warnings that the Windows builds now enforce. Otherwise warnings-as-errors-on-Windows is going to lead to a lot of frustration.

Yes, that was one of the reasons I didn't enable the warnings as errors in my previous bump to W4 on Windows, so I would have suggested that we added some additional warnings to OSX as well.

[lateralusX]

@AaronRobinsonMSFT we should also have dropped the section where we bump some warnings to errors in config.h.in, but I can do a PR during the day that take care of that as well as looking at doing some more warnings on OSX (the once that currently make sense, since we have still not enabled all needed warnings on Windows).

[AaronRobinsonMSFT]

@lateralusX Apologies in aggressively merging in the changes. Let me know how I can help move this forward to satisfy #66154. I really want to get the inner dev loop in a good state so no more violations crop up. Warnings C4018 and C4244 are very common and will take some time to address. Hopefully we can avoid adding more of them.