rustbuild: Remove --enable-llvm-clean-rebuild

configure

@@ -437,7 +437,6 @@ opt local-rust 0 "use an installed rustc rather than downloading a snapshot"
 opt local-rebuild 0 "assume local-rust matches the current version, for rebuilds; implies local-rust, and is implied if local-rust already matches the current version"
 opt llvm-static-stdcpp 0 "statically link to libstdc++ for LLVM"
 opt llvm-link-shared 0 "prefer shared linking to LLVM (llvm-config --link-shared)"
-opt llvm-clean-rebuild 0 "delete LLVM build directory on rebuild"
 opt rpath 1 "build rpaths into rustc itself"
 opt stage0-landing-pads 1 "enable landing pads during bootstrap with stage0"
 # This is used by the automation to produce single-target nightlies

src/bootstrap/config.rs

@@ -62,7 +62,6 @@ pub struct Config {
     pub llvm_targets: Option<String>,
     pub llvm_experimental_targets: Option<String>,
     pub llvm_link_jobs: Option<u32>,
-    pub llvm_clean_rebuild: bool,
 
     // rust codegen options
     pub rust_optimize: bool,
@@ -203,7 +202,6 @@ struct Llvm {
     targets: Option<String>,
     experimental_targets: Option<String>,
     link_jobs: Option<u32>,
-    clean_rebuild: Option<bool>,
 }
 
 #[derive(Deserialize, Default, Clone)]
@@ -352,7 +350,6 @@ impl Config {
             set(&mut config.llvm_release_debuginfo, llvm.release_debuginfo);
             set(&mut config.llvm_version_check, llvm.version_check);
             set(&mut config.llvm_static_stdcpp, llvm.static_libstdcpp);
-            set(&mut config.llvm_clean_rebuild, llvm.clean_rebuild);
             config.llvm_targets = llvm.targets.clone();
             config.llvm_experimental_targets = llvm.experimental_targets.clone();
             config.llvm_link_jobs = llvm.link_jobs;
@@ -477,7 +474,6 @@ impl Config {
                 ("LLVM_VERSION_CHECK", self.llvm_version_check),
                 ("LLVM_STATIC_STDCPP", self.llvm_static_stdcpp),
                 ("LLVM_LINK_SHARED", self.llvm_link_shared),
-                ("LLVM_CLEAN_REBUILD", self.llvm_clean_rebuild),
                 ("OPTIMIZE", self.rust_optimize),
                 ("DEBUG_ASSERTIONS", self.rust_debug_assertions),
                 ("DEBUGINFO", self.rust_debuginfo),

src/bootstrap/config.toml.example

@@ -69,11 +69,6 @@
 # controlled by rustbuild's -j parameter.
 #link-jobs = 0
 
-# Delete LLVM build directory on LLVM rebuild.
-# This option defaults to `false` for local development, but CI may want to
-# always perform clean full builds (possibly accelerated by (s)ccache).
-#clean-rebuild = false
-
 # =============================================================================
 # General build configuration options
 # =============================================================================

src/bootstrap/native.rs

@@ -80,9 +80,6 @@ impl Step for Llvm {
                 return
             }
         }
-        if build.config.llvm_clean_rebuild {
-            drop(fs::remove_dir_all(&out_dir));
-        }
 
         let _folder = build.fold_output(|| "llvm");
         println!("Building LLVM for {}", target);

src/ci/run.sh

@@ -31,7 +31,6 @@ RUST_CONFIGURE_ARGS="$RUST_CONFIGURE_ARGS --enable-sccache"
 RUST_CONFIGURE_ARGS="$RUST_CONFIGURE_ARGS --disable-manage-submodules"
 RUST_CONFIGURE_ARGS="$RUST_CONFIGURE_ARGS --enable-locked-deps"
 RUST_CONFIGURE_ARGS="$RUST_CONFIGURE_ARGS --enable-cargo-openssl-static"
-RUST_CONFIGURE_ARGS="$RUST_CONFIGURE_ARGS --enable-llvm-clean-rebuild"
 
 if [ "$DIST_SRC" = "" ]; then
   RUST_CONFIGURE_ARGS="$RUST_CONFIGURE_ARGS --disable-dist-src"