From 741978c5a73185b817cb2052413c0ef644dfad16 Mon Sep 17 00:00:00 2001 From: Samuel Holland Date: Fri, 8 Sep 2017 00:05:18 -0500 Subject: [PATCH 04/14] Use static native libraries when linking static executables On ELF targets like Linux, gcc/ld will create a dynamically-linked executable without warning, even when passed `-static`, when asked to link to a `.so`. Avoid this confusing and unintended behavior by always using the static version of libraries when trying to link static executables. --- compiler/rustc_codegen_ssa/src/back/link.rs | 20 ++++++++++++++++---- 1 file changed, 16 insertions(+), 4 deletions(-) diff --git a/compiler/rustc_codegen_ssa/src/back/link.rs b/compiler/rustc_codegen_ssa/src/back/link.rs index 6cce95427463c..ef3fcef87e2a0 100644 --- a/compiler/rustc_codegen_ssa/src/back/link.rs +++ b/compiler/rustc_codegen_ssa/src/back/link.rs @@ -2064,7 +2064,7 @@ fn linker_with_args<'a>( // together with their respective upstream crates, and in their originally specified order. // This may be slightly breaking due to our use of `--as-needed` and needs a crater run. if sess.opts.unstable_opts.link_native_libraries { - add_upstream_native_libraries(cmd, sess, codegen_results); + add_upstream_native_libraries(cmd, sess, codegen_results, crate_type); } // Link with the import library generated for any raw-dylib functions. @@ -2705,8 +2705,7 @@ fn add_upstream_rust_crates<'a>( } } -/// Link in all of our upstream crates' native dependencies. Remember that all of these upstream -/// native dependencies are all non-static dependencies. We've got two cases then: +/// Link in all of our upstream crates' native dependencies. We have two cases: /// /// 1. The upstream crate is an rlib. In this case we *must* link in the native dependency because /// the rlib is just an archive. @@ -2724,6 +2723,7 @@ fn add_upstream_native_libraries( cmd: &mut dyn Linker, sess: &Session, codegen_results: &CodegenResults, + crate_type: CrateType, ) { let mut last = (None, NativeLibKind::Unspecified, None); for &cnum in &codegen_results.crate_info.used_crates { @@ -2748,7 +2748,19 @@ fn add_upstream_native_libraries( NativeLibKind::Dylib { as_needed } => { cmd.link_dylib(name, verbatim, as_needed.unwrap_or(true)) } - NativeLibKind::Unspecified => cmd.link_dylib(name, verbatim, true), + NativeLibKind::Unspecified => { + // On some targets, like Linux, linking a static executable inhibits using + // dylibs at all. Force native libraries to be static, even if for example + // an upstream rlib was originally linked against a native shared library. + if crate_type == config::CrateType::Executable + && sess.crt_static(Some(crate_type)) + && !sess.target.options.crt_static_allows_dylibs + { + cmd.link_staticlib(name, verbatim) + } else { + cmd.link_dylib(name, verbatim, true) + } + }, NativeLibKind::Framework { as_needed } => { cmd.link_framework(name, as_needed.unwrap_or(true)) }