From db77e46b4967325cd05aa561979f04514efe1dfa Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Alex=20R=C3=B8nne=20Petersen?= <alex@alexrp.com>
Date: Wed, 5 Mar 2025 19:59:25 +0100
Subject: [PATCH] zig cc: Don't pass -mabi for assembly files when targeting
 arm.

Clang's integrated Arm assembler doesn't understand -mabi yet, so this results
in "unused command line argument" warnings when building musl code and glibc
stubs, for example.
---
 src/Compilation.zig | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/src/Compilation.zig b/src/Compilation.zig
index 12221ba3dc..bdb6507921 100644
--- a/src/Compilation.zig
+++ b/src/Compilation.zig
@@ -5631,7 +5631,10 @@ pub fn addCCArgs(
     }
 
     if (target_util.llvmMachineAbi(target)) |mabi| {
-        try argv.append(try std.fmt.allocPrint(arena, "-mabi={s}", .{mabi}));
+        // Clang's integrated Arm assembler doesn't support `-mabi` yet...
+        if (!(target.cpu.arch.isArm() and (ext == .assembly or ext == .assembly_with_cpp))) {
+            try argv.append(try std.fmt.allocPrint(arena, "-mabi={s}", .{mabi}));
+        }
     }
 
     // We might want to support -mfloat-abi=softfp for Arm and CSKY here in the future.