fix Issue 23387 - ImportC: identical structs defined in two C files l…

[WalterBright]

…ead to duplicate .init symbol on macOS

Note that the test should should compile them separately:

dmd imports/maker.i -c
dmd imports/freer.i -c
dmd test23387.d -c
dmd test23387.o freer.o maker.o

But I don't see a way to do that with the test runner.

[thewilsonator]

This is a backend change, cc @ibuclaw @kinke.

[ibuclaw]

Why is dmd even generating this symbol for C sources? The initializer is all zeros, no need to store that as a run-time symbol.

[RazvanN7]

ping @WalterBright

[dlang-bot]

Thanks for your pull request, @WalterBright!

Bugzilla references

Auto-close	Bugzilla	Severity	Description
✓	23387	normal	ImportC: identical structs defined in two C files lead to duplicate .init symbol on macOS

Testing this PR locally

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

dub run digger -- build "master + dmd#14541"

incorporated changes

[WalterBright]

I don't know what the test runner is asking for:

Test 'runnable/test23387.d' failed. The logged output:
/tmp/cirrus-ci-build/generated/freebsd/release/64/dmd -conf= -m64 -Irunnable  -fPIC  -odtest_results/runnable -c  runnable/test23387.d
/tmp/cirrus-ci-build/generated/freebsd/release/64/dmd -conf= -m64 -Irunnable  -fPIC  -odtest_results/runnable -c  runnable/imports/maker.i
/tmp/cirrus-ci-build/generated/freebsd/release/64/dmd -conf= -m64 -Irunnable  -fPIC  -odtest_results/runnable -c  runnable/imports/freer.i
/tmp/cirrus-ci-build/generated/freebsd/release/64/dmd -conf= -m64  -fPIC  -odtest_results/runnable -oftest_results/runnable/test23387_0 test_results/runnable/test23387.o test_results/runnable/maker.i test_results/runnable/freer.i
Error: cannot find input file `test_results/runnable/maker.i`
import path[0] = /tmp/cirrus-ci-build/compiler/test/../../druntime/import
import path[1] = /tmp/cirrus-ci-build/compiler/test/../../../phobos
==============================
Test 'runnable/test23387.d' failed: Expected rc == 0, but exited with rc == 1

[WalterBright]

@dkorpel do you know what is going on with the test runner?

[adamdruppe]

The C symbols shouldn't be separate anyway either. This is another case where the root fix (sticking to C semantics in importC; putting everything into one merged C namespace and collapsing compatible declarations) would solve several bugs at once, but by adding more and more special cases for individual issues, the tech debt grows instead of shrinks as issues are closed.

[WalterBright]

@adamdruppe I understand what you mean, but do not believe it is necessary.

[dkorpel]

@dkorpel do you know what is going on with the test runner?

No, but I can take a closer look tomorrow

[dkorpel]

The test runner doesn't replace the separately compiled ".i" extension to ".o", it only replaces ".d". I added a commit that should fix it.