Do not use relative paths to Rust source root in run-make tests

src/tools/run-make-support/src/lib.rs

@@ -87,6 +87,7 @@ pub fn htmldocck() -> Command {
     python
 }
 
+/// Path to the root rust-lang/rust source checkout.
 pub fn source_path() -> PathBuf {
     env_var("S").into()
 }

tests/run-make/alloc-no-oom-handling/rmake.rs

@@ -2,14 +2,14 @@
 // when the unstable no_global_oom_handling feature is turned on.
 // See https://github.com/rust-lang/rust/pull/84266
 
-use run_make_support::rustc;
+use run_make_support::{rustc, source_path};
 
 fn main() {
     rustc()
         .edition("2021")
         .arg("-Dwarnings")
         .crate_type("rlib")
-        .input("../../../library/alloc/src/lib.rs")
+        .input(source_path().join("library/alloc/src/lib.rs"))
         .cfg("no_global_oom_handling")
         .run();
 }

tests/run-make/alloc-no-rc/rmake.rs

@@ -2,14 +2,14 @@
 // when the unstable no_rc feature is turned on.
 // See https://github.com/rust-lang/rust/pull/84266
 
-use run_make_support::rustc;
+use run_make_support::{rustc, source_path};
 
 fn main() {
     rustc()
         .edition("2021")
         .arg("-Dwarnings")
         .crate_type("rlib")
-        .input("../../../library/alloc/src/lib.rs")
+        .input(source_path().join("library/alloc/src/lib.rs"))
         .cfg("no_rc")
         .run();
 }

tests/run-make/alloc-no-sync/rmake.rs

@@ -2,14 +2,14 @@
 // when the unstable no_sync feature is turned on.
 // See https://github.com/rust-lang/rust/pull/84266
 
-use run_make_support::rustc;
+use run_make_support::{rustc, source_path};
 
 fn main() {
     rustc()
         .edition("2021")
         .arg("-Dwarnings")
         .crate_type("rlib")
-        .input("../../../library/alloc/src/lib.rs")
+        .input(source_path().join("library/alloc/src/lib.rs"))
         .cfg("no_sync")
         .run();
 }

tests/run-make/core-no-fp-fmt-parse/rmake.rs

@@ -1,14 +1,14 @@
 // This test checks that the core library of Rust can be compiled without enabling
 // support for formatting and parsing floating-point numbers.
 
-use run_make_support::rustc;
+use run_make_support::{rustc, source_path};
 
 fn main() {
     rustc()
         .edition("2021")
         .arg("-Dwarnings")
         .crate_type("rlib")
-        .input("../../../library/core/src/lib.rs")
+        .input(source_path().join("library/core/src/lib.rs"))
         .cfg("no_fp_fmt_parse")
         .run();
 }

tests/run-make/core-no-oom-handling/rmake.rs

@@ -2,14 +2,14 @@
 // when the no_global_oom_handling feature is turned on.
 // See https://github.com/rust-lang/rust/pull/110649
 
-use run_make_support::{rustc, tmp_dir};
+use run_make_support::{rustc, tmp_dir, source_path};
 
 fn main() {
     rustc()
         .edition("2021")
         .arg("-Dwarnings")
         .crate_type("rlib")
-        .input("../../../library/core/src/lib.rs")
+        .input(source_path().join("library/core/src/lib.rs"))
         .sysroot(tmp_dir().join("fakeroot"))
         .cfg("no_global_oom_handling")
         .run();