Delete --whole-archive linking in libmscordaccore.so

[jkotas]

Fixes #115316

[Copilot]

Pull Request Overview

This PR removes the use of the --whole-archive linker flags in the libmscordaccore.so build, addressing issue #115316. It also refactors the DllMain entry points by making mscordac.cpp call an externally defined DllMain2 and removes a duplicated DllMain declaration from a header.

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated no comments.

File	Description
src/coreclr/dlls/mscordac/mscordac.cpp	Added a DllMain forwarding function that calls DllMain2 to streamline export management.
src/coreclr/dlls/mscordac/CMakeLists.txt	Removed whole-archive linker flags to prevent forcing inclusion of all objects, as discussed in #115316.
src/coreclr/debug/daccess/fntableaccess.h	Removed the redundant DllMain declaration to avoid conflicts and unnecessary duplication.
src/coreclr/debug/daccess/daccess.cpp	Replaced the DllMain definition with a DllMain2 definition, consolidating initialization logic.

Comments suppressed due to low confidence (4)

src/coreclr/dlls/mscordac/CMakeLists.txt:148

• The removal of the '--whole-archive' linker flags may affect the availability of certain exports. Please verify that all necessary symbols remain exported on all supported platforms after this change.

${START_WHOLE_ARCHIVE} # force all exports to be available

src/coreclr/debug/daccess/fntableaccess.h:96

• The removal of the DllMain declaration here helps avoid duplication, but ensure that no module relies on this declaration for proper linking or export.

BOOL WINAPI             DllMain(HINSTANCE hDLL, DWORD dwReason, LPVOID pReserved);

src/coreclr/dlls/mscordac/mscordac.cpp:14

• The DllMain function now forwards to DllMain2, which is defined elsewhere. Please ensure that this cross-file dependency is intentional and that DllMain2 is correctly linked on all target platforms.

BOOL WINAPI DllMain(HANDLE instance, DWORD reason, LPVOID reserved)

src/coreclr/debug/daccess/daccess.cpp:48

• Replacing DllMain with DllMain2 centralizes the initialization logic. Confirm that this revised entry point meets all platform-specific initialization requirements and that all callers are updated accordingly.

EXTERN_C BOOL WINAPI DllMain2(HANDLE instance, DWORD reason, LPVOID reserved)

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[jkotas]

I have verified that libmscordac.so is not missing any exports with this workaround. Also, it is only about 100kB smaller compared to --whole-archive linking.