gcc-lld mvp

ignore test if rust-lld not found

create ld -> rust-lld symlink at build time instead of run time

for testing in ci

copy instead of symlinking

remove linux check

test for linker, suggestions from bjorn3

fix overly restrictive lld matcher

use -Zgcc-ld flag instead of -Clinker-flavor

refactor code adding lld to gcc path

revert ci changes

suggestions from petrochenkov

rename gcc_ld to gcc-ld in dirs

2 files changed, 18 insertions, 0 deletions

diff --git a/compiler/rustc_session/src/config.rs b/compiler/rustc_session/src/config.rs
index 57522582683..2b547f8be92 100644
--- a/compiler/rustc_session/src/config.rs
+++ b/compiler/rustc_session/src/config.rs
@@ -2417,6 +2417,7 @@ impl PpMode {
 /// we have an opt-in scheme here, so one is hopefully forced to think about
 /// how the hash should be calculated when adding a new command-line argument.
 crate mod dep_tracking {
+    use super::LdImpl;
     use super::{
         CFGuard, CrateType, DebugInfo, ErrorOutputType, InstrumentCoverage, LinkerPluginLto,
         LtoCli, OptLevel, OutputTypes, Passes, SourceFileHashAlgorithm, SwitchWithOptPath,
@@ -2497,6 +2498,7 @@ crate mod dep_tracking {
         SymbolManglingVersion,
         SourceFileHashAlgorithm,
         TrimmedDefPaths,
+        Option<LdImpl>,
     );
 
     impl<T1, T2> DepTrackingHash for (T1, T2)
diff --git a/compiler/rustc_session/src/options.rs b/compiler/rustc_session/src/options.rs
index 58a53b3de6e..1946bfd78cc 100644
--- a/compiler/rustc_session/src/options.rs
+++ b/compiler/rustc_session/src/options.rs
@@ -370,6 +370,7 @@ mod desc {
     pub const parse_wasi_exec_model: &str = "either `command` or `reactor`";
     pub const parse_split_debuginfo: &str =
         "one of supported split-debuginfo modes (`off`, `packed`, or `unpacked`)";
+    pub const parse_gcc_ld: &str = "one of: no value, `lld`";
 }
 
 mod parse {
@@ -864,6 +865,15 @@ mod parse {
         }
         true
     }
+
+    crate fn parse_gcc_ld(slot: &mut Option<LdImpl>, v: Option<&str>) -> bool {
+        match v {
+            None => *slot = None,
+            Some("lld") => *slot = Some(LdImpl::Lld),
+            _ => return false,
+        }
+        true
+    }
 }
 
 options! {
@@ -1067,6 +1077,7 @@ options! {
         "set the optimization fuel quota for a crate"),
     function_sections: Option<bool> = (None, parse_opt_bool, [TRACKED],
         "whether each function should go in its own section"),
+    gcc_ld: Option<LdImpl> = (None, parse_gcc_ld, [TRACKED], "implementation of ld used by cc"),
     graphviz_dark_mode: bool = (false, parse_bool, [UNTRACKED],
         "use dark-themed colors in graphviz output (default: no)"),
     graphviz_font: String = ("Courier, monospace".to_string(), parse_string, [UNTRACKED],
@@ -1321,3 +1332,8 @@ pub enum WasiExecModel {
     Command,
     Reactor,
 }
+
+#[derive(Clone, Copy, Hash)]
+pub enum LdImpl {
+    Lld,
+}