Fix 15984 - [REG2.071] Interface contracts retrieve garbage instead of parameters

[SSoulaimane]

Copied from LDC func.d with slight modifications.

Essentially the parameters are passed explicitly to the contract functions. The major modification that I made from LDC is that I pass all the parameters by ref.

[thewilsonator]

cc @FeepingCreature

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Bugzilla references

Auto-close	Bugzilla	Severity	Description
✓	15984	regression	[REG2.071] Interface contracts retrieve garbage instead of parameters

Testing this PR locally

If you don't have a local development environment setup, you can use Digger to test this PR:

dub fetch digger
dub run digger -- build "stable + dmd#9782"

[thewilsonator]

../generated/linux/release/64/dmd -conf= -m64 -fPIC -g -lowmem -odtest_results -oftest_results/d_do_test tools/d_do_test.d
test_results/d_do_test.o: In function `_D3std5regex8internal6parser__T6ParserTAyaTSQBqQBpQBmQBg7CodeGenZQBi11parseEscapeMFNeZv':
/home/circleci/dmd/test/../../phobos/std/regex/internal/parser.d:983: undefined reference to `_D3std3uni__T5StackTkZQj3topMFNaNbNcNdNiNfZk'
collect2: error: ld returned 1 exit status
Error: linker exited with status 1
Makefile:202: recipe for target 'test_results/d_do_test' failed

[thewilsonator]

Also please target stable as this is a very critical bug fix for Funkwerk AG.

[SSoulaimane]

../generated/linux/release/64/dmd -conf= -m64 -fPIC -g -lowmem -odtest_results -oftest_results/d_do_test tools/d_do_test.d
test_results/d_do_test.o: In function `_D3std5regex8internal6parser__T6ParserTAyaTSQBqQBpQBmQBg7CodeGenZQBi11parseEscapeMFNeZv':
/home/circleci/dmd/test/../../phobos/std/regex/internal/parser.d:983: undefined reference to `_D3std3uni__T5StackTkZQj3topMFNaNbNcNdNiNfZk'
collect2: error: ld returned 1 exit status
Error: linker exited with status 1
Makefile:202: recipe for target 'test_results/d_do_test' failed

Rebased. Now it's gone.

Also please target stable as this is a very critical bug fix for Funkwerk AG.

Ok.

[thewilsonator]

Also Also if this is an ABI change it should have a changelog entry stating that. Can be added later.

[SSoulaimane]

Also Also if this is an ABI change it should have a changelog entry stating that.

Yes, it is an ABI change.

[wilzbach]

We don't require changelog entries for ABI changes, but as this is very important bug fix it wouldn't hurt at all and just help to increase the visibility and awareness of its fix.

[thewilsonator]

That too.

[kinke]

Also please target stable as this is a very critical bug fix for Funkwerk AG.

I don't think that was the right decision. It's a pretty big change in general, and ABI changes in a patch release are highly questionable IMO. The bug has been old, and a company welcoming a fix isn't a valid argument IMO.

Anyway, this caused unexpected trouble for LDC. One test also fails for DMD stable, so that's a regression from 2.086.0:

alias Bar = extern (C) void function(void*);

final class C
{
    void foo(Bar bar)
    in { assert(bar); }
    do {}
}

Error: function mod.C.foo.__require(ref void function(void*) bar) is not callable using argument types (extern (C) void function(void*))
       cannot pass argument bar of type extern (C) void function(void*) to parameter ref void function(void*) bar

I guess it's a syntaxCopy() issue (extern (C) linkage lost somewhere); TypeFunction.syntaxCopy() seems to copy the linkage though.

[SSoulaimane]

@kinke here #9843 is a fix for that.

[ibuclaw]

You forgot to clean-up the backend. With this, all the horrible special casing of require/ensure becomes unnecessary as there is no special frame needed anymore to get to parameters that were originally outside the contract context.

[SSoulaimane]

Yes it's still there.