Fix linking the outputs of the compilation #76
Merged
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Before this change, running link.exe on the output of the compilation produced `LINK : fatal error LNK1561: entry point must be defined`. This took longer to figure out than I would be willing to admit. There are two things at play - linker uses the presence of a method named `main` or `wmain` to choose between setting `wmainCRTStartup` or `mainCRTStartup` as the actual entrypoint of the application (C apps don't start with `main` - they start in the C runtime library that calls `main`). In dotnet#21 we deleted the `__fail_fast` method from main.cpp and then in dotnet#72 we also removed the compiler reference to the now non-existent symbol. The obscure result of that was that main.obj stopped being part of the linking set because nothing now references symbols from it. When linker looks for `main` or `wmain`, it only looks at object files that are already part of the linking set. As a result, linker didn't inject `wmainCRTStartup` as the entrypoint and we failed with the above message. It looks like the only way out is to hardcode the CRT implementation detail here. We were already hardcoding it, but for other reasons. We also need to set the subsystem since the autodetection is failing.
|
LGTM. I guess building the bootstrapper as .obj would fix this too, but it would be more complex change. |
jkotas
approved these changes
Aug 31, 2020
scalablecory
pushed a commit
that referenced
this pull request
Sep 22, 2020
Add server-side code for calculating and formatting the Retry Packet Integrity field, and update client code to calculate and verify the integrity value.
MichalStrehovsky
pushed a commit
to MichalStrehovsky/runtimelab
that referenced
this pull request
Oct 15, 2021
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
2 participants
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Before this change, running link.exe on the output of the compilation produced
LINK : fatal error LNK1561: entry point must be defined.This took longer to figure out than I would be willing to admit.
There are two things at play - linker uses the presence of a method named
mainorwmainto choose between settingwmainCRTStartupormainCRTStartupas the actual entrypoint of the application (C apps don't start withmain- they start in the C runtime library that callsmain).In #21 we deleted the
__fail_fastmethod from main.cpp and then in #72 we also removed the compiler reference to the now non-existent symbol. The obscure result of that was that main.obj stopped being part of the linking set because nothing now references symbols from it. When linker looks formainorwmain, it only looks at object files that are already part of the linking set.As a result, linker didn't inject
wmainCRTStartupas the entrypoint and we failed with the above message.It looks like the only way out is to hardcode the CRT implementation detail here. We were already hardcoding it, but for other reasons.
We also need to set the subsystem since the autodetection is failing.