From 236c0272667d69380d03984cfa8bad44b033fd69 Mon Sep 17 00:00:00 2001
From: Daniel Kolesa <daniel@octaforge.org>
Date: Tue, 21 Dec 2021 02:46:30 +0100
Subject: [PATCH 13/15] allow specifying native sysroot to use for linkage

This allows us to get around the linker attempting to use
incompatible libs.

diff --git a/src/bootstrap/src/core/builder.rs b/src/bootstrap/src/core/builder.rs
index 7f93fdc72..f52644b57 100644
--- a/src/bootstrap/src/core/builder.rs
+++ b/src/bootstrap/src/core/builder.rs
@@ -2429,6 +2429,10 @@ impl Cargo {
             self.hostflags.arg(&arg);
         }
 
+        if let Some(sysroot) = builder.native_sysroot(target) {
+            self.rustflags.arg(&format!("-Clink-args=--sysroot={}", sysroot.display()));
+        }
+
         if let Some(target_linker) = builder.linker(target) {
             let target = crate::envify(&target.triple);
             self.command.env(&format!("CARGO_TARGET_{target}_LINKER"), target_linker);
diff --git a/src/bootstrap/src/core/config/config.rs b/src/bootstrap/src/core/config/config.rs
index 3e1bc9a9a..e0038b9ac 100644
--- a/src/bootstrap/src/core/config/config.rs
+++ b/src/bootstrap/src/core/config/config.rs
@@ -575,6 +575,7 @@ pub struct Target {
     pub default_linker: Option<PathBuf>,
     pub linker: Option<PathBuf>,
     pub split_debuginfo: Option<SplitDebuginfo>,
+    pub sysroot: Option<PathBuf>,
     pub sanitizers: Option<bool>,
     pub profiler: Option<StringOrBool>,
     pub rpath: Option<bool>,
@@ -1135,6 +1136,7 @@ define_config! {
         default_linker: Option<PathBuf> = "default-linker",
         linker: Option<String> = "linker",
         split_debuginfo: Option<String> = "split-debuginfo",
+        sysroot: Option<String> = "sysroot",
         llvm_config: Option<String> = "llvm-config",
         llvm_has_rust_patches: Option<bool> = "llvm-has-rust-patches",
         llvm_filecheck: Option<String> = "llvm-filecheck",
@@ -1875,6 +1877,7 @@ impl Config {
                 target.ar = cfg.ar.map(PathBuf::from);
                 target.ranlib = cfg.ranlib.map(PathBuf::from);
                 target.linker = cfg.linker.map(PathBuf::from);
+                target.sysroot = cfg.sysroot.map(PathBuf::from);
                 target.crt_static = cfg.crt_static;
                 target.musl_root = cfg.musl_root.map(PathBuf::from);
                 target.musl_libdir = cfg.musl_libdir.map(PathBuf::from);
diff --git a/src/bootstrap/src/lib.rs b/src/bootstrap/src/lib.rs
index 5ed6b357e..0d4392dd8 100644
--- a/src/bootstrap/src/lib.rs
+++ b/src/bootstrap/src/lib.rs
@@ -1318,6 +1318,10 @@ impl Build {
             self.config.target_config.get(&target).and_then(|t| t.crt_static)
         }
     }
+    
+    fn native_sysroot(&self, target: TargetSelection) -> Option<&Path> {
+        self.config.target_config.get(&target).and_then(|c| c.sysroot.as_ref()).map(|p| &**p)
+    }
 
     /// Returns the "musl root" for this `target`, if defined
     fn musl_root(&self, target: TargetSelection) -> Option<&Path> {