I observe different outputs for diesels compile tests depending on whether I have the following ~/.cargo/config.toml file:

[target.]
linker = "clang"
rustflags = ["-C", "link-arg=-fuse-ld=/usr/bin/mold"]

If the file exists it seems like trybuild does not pass the --verbose flag to the compiler, if it doesn't exist it will pass that flag, which results in widely different output.

That's with trybuild 1.0.100 and rust 1.82.0 using the x86_64-unknown-linux-gnu target