Linker script support for rust_shared_library and cc_common.link
#2090
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| @@ -954,6 +954,12 @@ rust_shared_library = rule( | |||
| implementation = _rust_shared_library_impl, | |||
| attrs = dict( | |||
| _common_attrs.items() + _experimental_use_cc_common_link_attrs.items() + { | |||
| "linker_script": attr.label( | |||
| doc = dedent("""\ | |||
| Link script to forward into linker via rustc options. | |||
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nit: could you indent this and the next line so that they both start at +4 spaces relative to where the doc = on the previous line starts at
| if toolchain.target_os == "windows": | ||
| fail("Linking with cc_common.link for windows is currently not supported") | ||
| else: | ||
| user_link_flags = ["-Wl,--version-script={}".format(linker_script.path)] |
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Are these user_link_flags necessary? Looking a bit into --version-script, https://sourceware.org/binutils/docs/ld/VERSION.html, it seems it's for a special case of linker scripts. From reading up there, naively I'd expect that the linker will automatically pick up linker scripts by just directly listing the linker script as an input to the linker command line invocation, so I'd expect naively that just passing it to the additional_inputs will have the same effect?
Otherwise if that doesn't work for some reason, could we see if passing this via -T works: https://ftp.gnu.org/old-gnu/Manuals/ld-2.9.1/html_chapter/ld_3.html#:~:text=You%20may%20supply%20a%20command,use%20the%20%60%2DT'%20option.
We currently support linker scripts for
rust_binarybut not forrust_shared_library. This PR adds thelinker_scriptattribute torust_shared_libraryas well and tests for both.Additionally, this PR plumbs support for linker scripts when linking via
cc_common.link, and adds tests for it. I made it an explicit failure to use linker scripts on Windows withcc_common.linkas I'm not very fluent in how Windows works (I think I should have added a/DEF: script_pathto the command line and things would have just worked, but we don't even testcc_common.linkon Windows today, so I'd rather skip supporting it until we have somebody asking for it)