Auto merge of rust-lang#126494 - Kobzol:dont-strip-me-bro, r=<try>

Only strip `librustc_driver` and `libLLVM` during `x dist`

The strip invocation can be quite slow (~1-2 seconds), and it is executed on every compiler bootstrap refresh when debuginfo is turned off, which can make most bootstrap commands quite slow. Discussed [here](https://rust-lang.zulipchat.com/#narrow/stream/131828-t-compiler/topic/Only.20strip.20LLVM.2Frustc.20in.20the.20dist.20profile).

r? `@lqd`

Author: bors

src/bootstrap/src/core/build_steps/compile.rs

@@ -26,7 +26,7 @@ use crate::core::builder;
 use crate::core::builder::crate_description;
 use crate::core::builder::Cargo;
 use crate::core::builder::{Builder, Kind, PathSet, RunConfig, ShouldRun, Step, TaskPath};
-use crate::core::config::{DebuginfoLevel, LlvmLibunwind, RustcLto, TargetSelection};
+use crate::core::config::{LlvmLibunwind, RustcLto, TargetSelection};
 use crate::utils::helpers::{
     exe, get_clang_cl_resource_dir, is_debug_info, is_dylib, output, symlink_dir, t, up_to_date,
 };
@@ -970,19 +970,6 @@ impl Step for Rustc {
             true, // Only ship rustc_driver.so and .rmeta files, not all intermediate .rlib files.
         );
 
-        // When building `librustc_driver.so` (like `libLLVM.so`) on linux, it can contain
-        // unexpected debuginfo from dependencies, for example from the C++ standard library used in
-        // our LLVM wrapper. Unless we're explicitly requesting `librustc_driver` to be built with
-        // debuginfo (via the debuginfo level of the executables using it): strip this debuginfo
-        // away after the fact.
-        if builder.config.rust_debuginfo_level_rustc == DebuginfoLevel::None
-            && builder.config.rust_debuginfo_level_tools == DebuginfoLevel::None
-        {
-            let target_root_dir = stamp.parent().unwrap();
-            let rustc_driver = target_root_dir.join("librustc_driver.so");
-            strip_debug(builder, target, &rustc_driver);
-        }
-
         builder.ensure(RustcLink::from_rustc(
             self,
             builder.compiler(compiler.stage, builder.config.build),
@@ -2142,6 +2129,7 @@ pub enum CargoMessage<'a> {
     BuildFinished,
 }
 
+/// Strips debug symbols from the given library or executable **in-place**.
 pub fn strip_debug(builder: &Builder<'_>, target: TargetSelection, path: &Path) {
     // FIXME: to make things simpler for now, limit this to the host and target where we know
     // `strip -g` is both available and will fix the issue, i.e. on a x64 linux host that is not

src/bootstrap/src/core/build_steps/dist.rs

@@ -24,13 +24,14 @@ use crate::core::build_steps::doc::DocumentationFormat;
 use crate::core::build_steps::llvm;
 use crate::core::build_steps::tool::{self, Tool};
 use crate::core::builder::{Builder, Kind, RunConfig, ShouldRun, Step};
-use crate::core::config::TargetSelection;
+use crate::core::config::{DebuginfoLevel, TargetSelection};
 use crate::utils::channel::{self, Info};
 use crate::utils::helpers::{
     exe, is_dylib, move_file, output, t, target_supports_cranelift_backend, timeit,
 };
 use crate::utils::tarball::{GeneratedTarball, OverlayKind, Tarball};
 use crate::{Compiler, DependencyType, Mode, LLVM_TOOLS};
+use crate::core::build_steps::compile::strip_debug;
 
 pub fn pkgname(builder: &Builder<'_>, component: &str) -> String {
     format!("{}-{}", component, builder.rust_package_vers())
@@ -433,14 +434,26 @@ impl Step for Rustc {
 
             // Copy runtime DLLs needed by the compiler
             if libdir_relative.to_str() != Some("bin") {
+                let target_libdir = image.join("lib");
                 let libdir = builder.rustc_libdir(compiler);
                 for entry in builder.read_dir(&libdir) {
                     let name = entry.file_name();
                     if let Some(s) = name.to_str() {
                         if is_dylib(s) {
                             // Don't use custom libdir here because ^lib/ will be resolved again
                             // with installer
-                            builder.install(&entry.path(), &image.join("lib"), 0o644);
+                            builder.install(&entry.path(), &target_libdir, 0o644);
+
+                            // When building `librustc_driver.so` (like `libLLVM.so`) on linux, it can contain
+                            // unexpected debuginfo from dependencies, for example from the C++ standard library used in
+                            // our LLVM wrapper. Unless we're explicitly requesting `librustc_driver` to be built with
+                            // debuginfo (via the debuginfo level of the executables using it): strip this debuginfo
+                            // away after the fact when we distribute it.
+                            if s.starts_with("librustc_driver") &&
+                                builder.config.rust_debuginfo_level_rustc == DebuginfoLevel::None &&
+                                builder.config.rust_debuginfo_level_tools == DebuginfoLevel::None {
+                                strip_debug(builder, host, &target_libdir.join(name));
+                            }
                         }
                     }
                 }