Reduce CoreCLR PAL

[janvorli]

I have discovered some unused functions in the coreclr PAL. So I have removed it from the PAL and also removed some unused stuf from the coreclr that I have found along the way.
I have also replace the DeleteFile by standard remove function.
The CreatePipe is not used by any code using the PAL except for the PAL tests. But I had to keep it to
preserve CreateProcess tests without refactoring. So I have at least removed it from the pal.h to prevent future usage.
I have also modified couple of PAL tests to get rid of SetEndOfFile API usage that was removed for tests where it made sense to preserve them.

[jkotas]

Thanks!

[AaronRobinsonMSFT]

[jkotas]

This introduced a build break in Mono:

2022-10-11T04:38:50.1127810Z [ 87%] Building CXX object dlls/mscordbi/utilcode/CMakeFiles/utilcode_obj.dir/clrhost_nodependencies.cpp.o
2022-10-11T04:38:50.1205136Z /__w/1/s/src/mono/dlls/dbgshim/dbgshim.cpp:122:9: error: use of undeclared identifier '_putenv'
2022-10-11T04:38:50.1207257Z putenv("MONO_ENV_OPTIONS='--debugger-agent=transport=dt_socket,address=127.0.0.1:pid_based,server=n,suspend=y,loglevel=10,timeout=100000'");
2022-10-11T04:38:50.1208250Z ^
2022-10-11T04:38:50.1341137Z /__w/1/s/src/mono/dlls/dbgshim/dbgshim.cpp:19:16: note: expanded from macro 'putenv'
2022-10-11T04:38:50.1346925Z #define putenv _putenv
2022-10-11T04:38:50.1358557Z ^

I am going to revert this PR.

[vargaz]

Why didn't CI pick up the build breakage ?

[am11]

@vargaz, the change path evaluation (responsible for triggering CI legs) is missing src/coreclr/pal and src/coreclr/utilcode from:

runtime/eng/pipelines/common/evaluate-default-paths.yml

Lines 61 to 62 in 3435b39

	- subset: mono_excluding_wasm
	include:

Since mono desktop depend on coreclr PAL (for corehost), I think we should add those paths in the list which affects mono.

Docs:

runtime/eng/pipelines/evaluate-changed-paths.sh

Lines 1 to 18 in 3435b39

	#!/usr/bin/env bash
	:'
	Scenarios:
	1. exclude paths are specified
	Will include all paths except the ones in the exclude list.
	2. include paths are specified
	Will only include paths specified in the list.
	3. exclude + include:
	1st we evaluate changes for all paths except ones in excluded list. If we can not find
	any applicable changes like that, then we evaluate changes for included paths
	if any of these two finds changes, then a variable will be set to true.
	In order to consume this variable in a yaml pipeline, reference it via: $[ dependencies.<JobName>.outputs["<StepName>_<subset>.containschange"] ]
	Example:
	-difftarget ''HEAD^1'' -subset coreclr -includepaths ''src/libraries/System.Private.CoreLib/*'' -excludepaths ''src/libraries/*+src/installer/*''
	This example will include ALL path changes except the ones under src/libraries/*!System.Private.CoreLib/*
	'

cc @akoeplinger

[jkotas]

the change path evaluation (responsible for triggering CI legs) is missing src/coreclr/pal and src/coreclr/utilcode from:

It is more directories than that: https://github.com/dotnet/runtime/blob/main/src/mono/dlls/mscordbi/CMakeLists.txt#L31-L43

[janvorli]

Ouch, I had no idea that anything in mono uses coreclr PAL.

[AaronRobinsonMSFT]

Ouch, I had no idea that anything in mono uses coreclr PAL.

Agreed. That seems wrong. Shared code really needs to be moved up to src/native.

@jkotas Was it just putenv or did you find others?

[jkotas]

That seems wrong. Shared code really needs to be moved up to src/native.

I think there is larger problem with how the ICorDebug Mono implementation is factored. The first questions to ask would be where it is used and how it is tested and where we want to move it going forward, and only then worry about mechanics.

Was it just putenv or did you find others?

The build break error was just about putenv, but I do not know whether there is more hiding behind it.

[akoeplinger]

/cc @lambdageek@lateralusX

[janvorli]

I'll try to build Mono and see if anything else breaks. The _putenv is cheap to put back for now as it is just a thin wrapper around EnvironPutenv that is used at few other places.

[janvorli]

I have tried to build mono locally off my branch and it all passed. @jkotas can you point me to the job that has failed with that error?

[akoeplinger]

@janvorli you need to build the mono.mscordbi subset.

[janvorli]

@akoeplinger I have tried that too before and it succeeded. However, it seems it doesn't build anything native. I've even tried a clean build.