Pass the era's assembler version to rucc

crates/rk-shim/src/bringup.rs

@@ -68,13 +68,16 @@ const NEWER_THAN_BRINGUP: &[&str] = &["-fzero-init-padding-bits="];
 
 /// The arguments a call hands to its compiler.
 ///
-/// rk puts the era's persona in `CC` as `-fgnuc-version=`, which only rucc knows. GCC refuses
+/// rk puts the era's persona in `CC` as `-fgnuc-version=` and `-fgnu-as-version=`, which only rucc
+/// knows. GCC refuses
 /// it, so a delegated call leaves it out, along with the flags in [`NEWER_THAN_BRINGUP`]. Every
 /// other argument goes through as kbuild wrote it.
 #[must_use]
 pub fn passed_on(args: &[String], delegated: bool) -> Vec<String> {
     let refused = |a: &str| {
-        a.starts_with("-fgnuc-version=") || NEWER_THAN_BRINGUP.iter().any(|f| a.starts_with(f))
+        a.starts_with("-fgnuc-version=")
+            || a.starts_with("-fgnu-as-version=")
+            || NEWER_THAN_BRINGUP.iter().any(|f| a.starts_with(f))
     };
     args.iter()
         .filter(|a| !(delegated && refused(a)))
@@ -177,10 +180,18 @@ mod tests {
 
     #[test]
     fn the_persona_is_not_passed_on_to_the_other_compiler() {
-        let args: Vec<String> = ["-fgnuc-version=14.2.0", "-m16", "-c", "-o", "a.o", "a.S"]
-            .iter()
-            .map(|s| (*s).to_string())
-            .collect();
+        let args: Vec<String> = [
+            "-fgnuc-version=14.2.0",
+            "-fgnu-as-version=2.44",
+            "-m16",
+            "-c",
+            "-o",
+            "a.o",
+            "a.S",
+        ]
+        .iter()
+        .map(|s| (*s).to_string())
+        .collect();
         assert_eq!(passed_on(&args, true), ["-m16", "-c", "-o", "a.o", "a.S"]);
         assert_eq!(passed_on(&args, false), args, "rucc keeps it");
     }

crates/rk/src/build.rs

@@ -3,8 +3,9 @@
 //! The tree is never written to. kbuild's output goes under `O=`, and the compiler is the shim,
 //! copied into the build directory with an `rk-cc.toml` naming the real compiler, so that every
 //! sub make, including the ones that clean their environment, still goes through it. When the
-//! compiler is rucc, the era's persona is part of `CC`, as `rk-cc -fgnuc-version=14.2.0`, which
-//! is what a user building by hand would write too.
+//! compiler is rucc, the era's persona is part of `CC`, as `rk-cc -fgnuc-version=14.2.0
+//! -fgnu-as-version=2.44`, which is what a user building by hand would write too. The second one
+//! is what `scripts/as-version.sh` reads, so `CONFIG_AS_VERSION` matches the reference's binutils.
 //!
 //! Nothing else is added to the command line, with one exception that changes no code:
 //! `--stack-usage` passes `KCFLAGS=-fstack-usage`, as the kernel's own `scripts/stackusage` does,
@@ -524,7 +525,10 @@ pub fn run(plan: &Plan) -> Result<Outcome, String> {
         .map_err(|e| format!("writing the shim's settings: {e}"))?;
 
     let persona = if plan.compiler.rucc {
-        vec![format!("-fgnuc-version={}", plan.era.gnuc)]
+        vec![
+            format!("-fgnuc-version={}", plan.era.gnuc),
+            format!("-fgnu-as-version={}", plan.era.gnu_as),
+        ]
     } else {
         Vec::new()
     };

crates/rk/src/flags.rs

@@ -98,6 +98,7 @@ pub fn normalize(words: &[String], dirs: &[(&str, &str)]) -> Vec<String> {
             continue;
         }
         if word.starts_with("-fgnuc-version=")
+            || word.starts_with("-fgnu-as-version=")
             || word.starts_with("-Wp,-MD,")
             || word.starts_with("-Wp,-MMD,")
             || matches!(word.as_str(), "-MD" | "-MMD")

crates/rk/src/probes.rs

@@ -26,7 +26,10 @@ pub fn question(record: &CompileRecord) -> String {
             args.next();
             continue;
         }
-        if arg.starts_with("-fgnuc-version=") || (arg.starts_with("-o") && arg.len() > 2) {
+        if arg.starts_with("-fgnuc-version=")
+            || arg.starts_with("-fgnu-as-version=")
+            || (arg.starts_with("-o") && arg.len() > 2)
+        {
             continue;
         }
         if arg.contains(".tmp_") {

crates/rk/src/syntax.rs

@@ -46,6 +46,7 @@ pub fn replay_args(record: &CompileRecord, extra: &[String]) -> Vec<String> {
             || arg.starts_with("-Wp,-MD,")
             || arg.starts_with("-Wp,-MMD,")
             || arg.starts_with("-fgnuc-version=")
+            || arg.starts_with("-fgnu-as-version=")
         {
             continue;
         }