linker: Allow calling into unimplemented forward function declarations #544
Conversation
This file contains 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
ti-mo
force-pushed
the
tb/linker-fwd-decl
branch
from
fa64336
to
a0137c1
Compare
lmb
approved these changes
Jan 21, 2022
|
Adding errUnsatisfiedProgram in a follow-up, we need to tell the two apart. Signed-off-by: Timo Beckers <timo@isovalent.com>
…alls Allow the caller to make forward function declarations in C and provide the final implementation after the CollectionSpec has been loaded. Fix a papercut where NewProgram panics when called with a nil spec. Signed-off-by: Timo Beckers <timo@isovalent.com>
This test makes sure the linker allows calls into missing symbols so that they can be provided by the caller after the CollectionSpec has been emitted.
ti-mo
force-pushed
the
tb/linker-fwd-decl
branch
from
a0137c1
to
0757a31
Compare
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
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Outdated suggestions cannot be applied.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.
After #508, the linker became more restrictive regarding jumps to symbols that don't appear in the same section, as these usually mean a function in another section is called. One notable exception to this rule is forward function declarations that are left unimplemented.
This patch adds the possibility for the caller to provide an implementation for these symbols after the CollectionSpec has been emitted. Instead, throw an error when the ProgramSpec is instantiated into a Program.
Fixes #531
@arthurfabre Please check if this works as expected for your production code.