`-C instrument-coverage` does not work with `crate-type = ["dylib"]` dependency on windows-msvc about rust

[bjorn3]

Could this be related to libstd getting dynamically linked without being built with -Cinstrument-coverage itself? Maybe try if RUSTFLAGS="-Cprefer-dynamic" works for a regular crate without any dylibs other than libstd involved.

[taiki-e]

Maybe try if RUSTFLAGS="-Cprefer-dynamic" works for a regular crate without any dylibs other than libstd involved.

I tried with setting the dependency crate-type back to default and with -Cprefer-dynamic enabled, but no error occurred.

-[lib]
-crate-type = ["dylib"]
+#[lib]
+#crate-type = ["dylib"]

$ $env:RUSTFLAGS="-C instrument-coverage -Cprefer-dynamic"; cargo test --tests -v
   Compiling dylib v0.1.0 (C:\Users\taiki\projects\tmp\coverage_debugging\dylib)
     Running `rustc --crate-name dylib --edition=2021 dylib\src\lib.rs --error-format=json --json=diagnostic-rendered-ansi,artifacts,future-incompat --diagnostic-width=183 --crate-type lib --emit=dep-info,metadata,link -C embed-bitcode=no -C debuginfo=2 -C metadata=66b504ff4471d6a2 -C extra-filename=-66b504ff4471d6a2 --out-dir C:\Users\taiki\projects\tmp\coverage_debugging\target\debug\deps -C incremental=C:\Users\taiki\projects\tmp\coverage_debugging\target\debug\incremental -L dependency=C:\Users\taiki\projects\tmp\coverage_debugging\target\debug\deps -C instrument-coverage -Cprefer-dynamic`
   Compiling repro v0.1.0 (C:\Users\taiki\projects\tmp\coverage_debugging)
     Running `rustc --crate-name repro --edition=2021 src\lib.rs --error-format=json --json=diagnostic-rendered-ansi,artifacts,future-incompat --diagnostic-width=183 --emit=dep-info,link -C embed-bitcode=no -C debuginfo=2 --test -C metadata=c71f36c1d55bce77 -C extra-filename=-c71f36c1d55bce77 --out-dir C:\Users\taiki\projects\tmp\coverage_debugging\target\debug\deps -C incremental=C:\Users\taiki\projects\tmp\coverage_debugging\target\debug\incremental -L dependency=C:\Users\taiki\projects\tmp\coverage_debugging\target\debug\deps --extern dylib=C:\Users\taiki\projects\tmp\coverage_debugging\target\debug\deps\libdylib-66b504ff4471d6a2.rlib -C instrument-coverage -Cprefer-dynamic`
    Finished `test` profile [unoptimized + debuginfo] target(s) in 0.42s
     Running `C:\Users\taiki\projects\tmp\coverage_debugging\target\debug\deps\repro-c71f36c1d55bce77.exe`

running 1 test
test test::test_double ... ok

test result: ok. 1 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.00s