[Pkg-rust-maintainers] Bug#973387: rust-bindgen: autopkg test failures for new featuresets.

[peter green]

Package: rust-bindgen
Version: 0.55.1-1
Severity: serious

rust-bindgen 0.55.1 introduced two new featuresets. The autopkgtests for these featuresets are failing
For the "runtime" feature we have.

 > ---- test::commandline_multiple_headers stdout ----
 > bindgen tests/headers/16-byte-alignment.h --rust-target 1.40 --no-derive-default --generate functions,types,vars,methods,constructors,destructors -- -include tests/headers/char.h -include tests/headers/func_ptr.h
 > error: header 'tests/headers/16-byte-alignment.h' does not exist.
<--snip-->
 > failures:
 >     test::commandline_multiple_headers
 >
 > test result: FAILED. 0 passed; 1 failed; 0 ignored; 0 measured; 0 filtered out
 >
 > error: test failed, to rerun pass '--bin bindgen'
 > autopkgtest [16:17:20]: test librust-bindgen+runtime-dev: -----------------------]
 > autopkgtest [16:17:20]: test librust-bindgen+runtime-dev:  - - - - - - - - - - results - - - - - - - - - -
 > librust-bindgen+runtime-dev FAIL non-zero exit status 101
This failure looks similar to the failures for other featuresets where the tests are already marked as broken.
As such I think it makes sense to mark this one as broken too.

For the "static" feature we have.

 > [clang-sys 1.0.1] thread 'main' panicked at 'could not find any static libraries', /tmp/tmp.DRdlTsehqq/registry/clang-sys-1.0.1/build/static.rs:96:9
<--snip-->
 > error: build failed
 > autopkgtest [16:17:33]: test librust-bindgen+static-dev: -----------------------]
 > autopkgtest [16:17:33]: test librust-bindgen+static-dev:  - - - - - - - - - - results - - - - - - - - - -
 > librust-bindgen+static-dev FAIL non-zero exit status 101

It appears to me that the failure is in the static feature of the clang-sys package. Unfortunately it
seems that the clang-sys autopkgtests do not test the static feature. The "all features" test is
marked as broken because "The `runtime` and `static` features can't be combined (see build.rs)"
and there does not seem to be a separate test for the "static" feature in the rust-clang-sys
autopkgtests.

It looks to me like the underlying reason for the failure is that debians libclang-9-dev package does
not appear to provide a libclang.a file. It does however provide a number of other .a files which look
like they may be bits of libclang. I don't see a .pc file in the libclang-9-dev package either. I'll send
a seperate mail to the llvm maintainers about that.