diff --git a/lib/std/Thread.zig b/lib/std/Thread.zig
index 25f9146bb0aa6ce8cb6ae4d3744788002bdf2413..59b8a992b1db044fcaf122e8403b6be3f3d63bc6 100644
--- a/lib/std/Thread.zig
+++ b/lib/std/Thread.zig
@@ -1220,6 +1220,16 @@ const LinuxThreadImpl = struct {
                     : [ptr] "{$16}" (@intFromPtr(self.mapped.ptr)),
                       [len] "{$17}" (self.mapped.len),
                 ),
+                .arc, .arceb => asm volatile (
+                    \\ mov r8, 215 # SYS_munmap
+                    \\ trap_s 0
+                    \\ mov r8, 93 # SYS_exit
+                    \\ mov r0, 0
+                    \\ trap_s 0
+                    :
+                    : [ptr] "{r0}" (@intFromPtr(self.mapped.ptr)),
+                      [len] "{r1}" (self.mapped.len),
+                ),
                 .hexagon => asm volatile (
                     \\  r6 = #215 // SYS_munmap
                     \\  trap0(#1)
diff --git a/lib/std/debug/cpu_context.zig b/lib/std/debug/cpu_context.zig
index b4b3e62c5cd960c149c34f4f34220d3e88d3447c..a1b530a9b19f2233e5f5efa9e3b2f408c52f703c 100644
--- a/lib/std/debug/cpu_context.zig
+++ b/lib/std/debug/cpu_context.zig
@@ -50,7 +50,7 @@ pub fn fromPosixSignalContext(ctx_ptr: ?*const anyopaque) ?Native {
         };
 
         // I have no idea why the kernel is storing these registers in such a bizarre order...
-        std.mem.reverse(native.r[0..]);
+        std.mem.reverse(u32, native.r[0..]);
 
         return native;
     } else if (native_arch == .loongarch32 and native_os == .linux) {