std.os.linux: remove some pointless asm clobbers in naked fns

Author: alexrp

lib/std/os/linux/arm.zig

@@ -134,12 +134,12 @@ pub fn restore() callconv(.naked) noreturn {
             \\ svc #0
             :
             : [number] "I" (@intFromEnum(SYS.sigreturn)),
-            : .{ .memory = true }),
+        ),
         else => asm volatile (
             \\ svc #0
             :
             : [number] "{r7}" (@intFromEnum(SYS.sigreturn)),
-            : .{ .memory = true }),
+        ),
     }
 }
 

lib/std/os/linux/powerpc.zig

@@ -254,7 +254,7 @@ pub fn restore_rt() callconv(.naked) noreturn {
             :
             : [number] "i" (@intFromEnum(SYS.rt_sigreturn)),
         ),
-        else => _ = asm volatile (
+        else => asm volatile (
             \\ sc
             :
             : [number] "{r0}" (@intFromEnum(SYS.rt_sigreturn)),

lib/std/os/linux/powerpc64.zig

@@ -239,7 +239,7 @@ pub fn restore_rt() callconv(.naked) noreturn {
             :
             : [number] "i" (@intFromEnum(SYS.rt_sigreturn)),
         ),
-        else => _ = asm volatile (
+        else => asm volatile (
             \\ sc
             :
             : [number] "{r0}" (@intFromEnum(SYS.rt_sigreturn)),

lib/std/os/linux/x86.zig

@@ -175,12 +175,12 @@ pub fn restore() callconv(.naked) noreturn {
             \\ int $0x80
             :
             : [number] "i" (@intFromEnum(SYS.sigreturn)),
-            : .{ .memory = true }),
+        ),
         else => asm volatile (
             \\ int $0x80
             :
             : [number] "{eax}" (@intFromEnum(SYS.sigreturn)),
-            : .{ .memory = true }),
+        ),
     }
 }