diff --git a/lib/std/os/linux/aarch64.zig b/lib/std/os/linux/aarch64.zig
index 431097feccf104eba84a3f347fac6fe29ae1eb57..5381def39f634c526d0cef748c8e89306a494544 100644
--- a/lib/std/os/linux/aarch64.zig
+++ b/lib/std/os/linux/aarch64.zig
@@ -152,19 +152,12 @@ pub fn clone() callconv(.naked) u64 {
 pub const restore = restore_rt;
 
 pub fn restore_rt() callconv(.naked) noreturn {
-    switch (builtin.zig_backend) {
-        .stage2_c => asm volatile (
-            \\ mov w8, %[number]
-            \\ svc #0
-            :
-            : [number] "i" (@backingInt(SYS.rt_sigreturn)),
-        ),
-        else => asm volatile (
-            \\ svc #0
-            :
-            : [number] "{x8}" (@backingInt(SYS.rt_sigreturn)),
-        ),
-    }
+    asm volatile (
+        \\ mov w8, %[number]
+        \\ svc #0
+        :
+        : [number] "i" (@backingInt(SYS.rt_sigreturn)),
+    );
 }
 
 pub const VDSO = struct {
diff --git a/lib/std/os/linux/arc.zig b/lib/std/os/linux/arc.zig
index 8721de28f9922068d405cda98f4b64da474b69ab..e2c0785ffc53158eb4b6e17656bd4e95c155481f 100644
--- a/lib/std/os/linux/arc.zig
+++ b/lib/std/os/linux/arc.zig
@@ -153,19 +153,12 @@ pub fn clone() callconv(.naked) u32 {
 pub const restore = restore_rt;
 
 pub fn restore_rt() callconv(.naked) noreturn {
-    switch (builtin.zig_backend) {
-        .stage2_c => asm volatile (
-            \\ mov r8, %[number]
-            \\ trap_s 0
-            :
-            : [number] "I" (@backingInt(SYS.rt_sigreturn)),
-        ),
-        else => asm volatile (
-            \\ trap_s 0
-            :
-            : [number] "{r8}" (@backingInt(SYS.rt_sigreturn)),
-        ),
-    }
+    asm volatile (
+        \\ mov r8, %[number]
+        \\ trap_s 0
+        :
+        : [number] "I" (@backingInt(SYS.rt_sigreturn)),
+    );
 }
 
 pub const time_t = i64;
diff --git a/lib/std/os/linux/arm.zig b/lib/std/os/linux/arm.zig
index d198c03748a9ad119a477b0de580770d441396ea..7d7631b36c6380474e540f2c43d2c59900e319da 100644
--- a/lib/std/os/linux/arm.zig
+++ b/lib/std/os/linux/arm.zig
@@ -146,35 +146,21 @@ pub fn clone() callconv(.naked) u32 {
 }
 
 pub fn restore() callconv(.naked) noreturn {
-    switch (builtin.zig_backend) {
-        .stage2_c => asm volatile (
-            \\ mov r7, %[number]
-            \\ svc #0
-            :
-            : [number] "I" (@backingInt(SYS.sigreturn)),
-        ),
-        else => asm volatile (
-            \\ svc #0
-            :
-            : [number] "{r7}" (@backingInt(SYS.sigreturn)),
-        ),
-    }
+    asm volatile (
+        \\ mov r7, %[number]
+        \\ svc #0
+        :
+        : [number] "I" (@backingInt(SYS.sigreturn)),
+    );
 }
 
 pub fn restore_rt() callconv(.naked) noreturn {
-    switch (builtin.zig_backend) {
-        .stage2_c => asm volatile (
-            \\ mov r7, %[number]
-            \\ svc #0
-            :
-            : [number] "I" (@backingInt(SYS.rt_sigreturn)),
-        ),
-        else => asm volatile (
-            \\ svc #0
-            :
-            : [number] "{r7}" (@backingInt(SYS.rt_sigreturn)),
-        ),
-    }
+    asm volatile (
+        \\ mov r7, %[number]
+        \\ svc #0
+        :
+        : [number] "I" (@backingInt(SYS.rt_sigreturn)),
+    );
 }
 
 pub const VDSO = struct {
diff --git a/lib/std/os/linux/powerpc.zig b/lib/std/os/linux/powerpc.zig
index ae2574e52b07bd4856bfee02bf6fbeb7c1ae3e43..6d47674234948a9a6e3fb0070507e852bf418656 100644
--- a/lib/std/os/linux/powerpc.zig
+++ b/lib/std/os/linux/powerpc.zig
@@ -263,35 +263,21 @@ pub fn clone() callconv(.naked) u32 {
 }
 
 pub fn restore() callconv(.naked) noreturn {
-    switch (builtin.zig_backend) {
-        .stage2_c => asm volatile (
-            \\ li 0, %[number]
-            \\ sc
-            :
-            : [number] "i" (@backingInt(SYS.sigreturn)),
-        ),
-        else => asm volatile (
-            \\ sc
-            :
-            : [number] "{r0}" (@backingInt(SYS.sigreturn)),
-        ),
-    }
+    asm volatile (
+        \\ li 0, %[number]
+        \\ sc
+        :
+        : [number] "i" (@backingInt(SYS.sigreturn)),
+    );
 }
 
 pub fn restore_rt() callconv(.naked) noreturn {
-    switch (builtin.zig_backend) {
-        .stage2_c => asm volatile (
-            \\ li 0, %[number]
-            \\ sc
-            :
-            : [number] "i" (@backingInt(SYS.rt_sigreturn)),
-        ),
-        else => asm volatile (
-            \\ sc
-            :
-            : [number] "{r0}" (@backingInt(SYS.rt_sigreturn)),
-        ),
-    }
+    asm volatile (
+        \\ li 0, %[number]
+        \\ sc
+        :
+        : [number] "i" (@backingInt(SYS.rt_sigreturn)),
+    );
 }
 
 pub const VDSO = struct {
diff --git a/lib/std/os/linux/powerpc64.zig b/lib/std/os/linux/powerpc64.zig
index 5dd1fc9a9d8163ec50b37e58749a63d2eaf5312a..d6f488cad409bef8f7ab9ce082eda5e23ca7f35e 100644
--- a/lib/std/os/linux/powerpc64.zig
+++ b/lib/std/os/linux/powerpc64.zig
@@ -247,35 +247,21 @@ pub fn clone() callconv(.naked) u64 {
 }
 
 pub fn restore() callconv(.naked) noreturn {
-    switch (builtin.zig_backend) {
-        .stage2_c => asm volatile (
-            \\ li 0, %[number]
-            \\ sc
-            :
-            : [number] "i" (@backingInt(SYS.sigreturn)),
-        ),
-        else => asm volatile (
-            \\ sc
-            :
-            : [number] "{r0}" (@backingInt(SYS.sigreturn)),
-        ),
-    }
+    asm volatile (
+        \\ li 0, %[number]
+        \\ sc
+        :
+        : [number] "i" (@backingInt(SYS.sigreturn)),
+    );
 }
 
 pub fn restore_rt() callconv(.naked) noreturn {
-    switch (builtin.zig_backend) {
-        .stage2_c => asm volatile (
-            \\ li 0, %[number]
-            \\ sc
-            :
-            : [number] "i" (@backingInt(SYS.rt_sigreturn)),
-        ),
-        else => asm volatile (
-            \\ sc
-            :
-            : [number] "{r0}" (@backingInt(SYS.rt_sigreturn)),
-        ),
-    }
+    asm volatile (
+        \\ li 0, %[number]
+        \\ sc
+        :
+        : [number] "i" (@backingInt(SYS.rt_sigreturn)),
+    );
 }
 
 pub const VDSO = struct {
diff --git a/lib/std/os/linux/s390x.zig b/lib/std/os/linux/s390x.zig
index 3c44beeb8df7bb5d7f0d7d7fb13f3c35c840da01..4f90ad2081a613d8416464df25a98c8529b9d3a9 100644
--- a/lib/std/os/linux/s390x.zig
+++ b/lib/std/os/linux/s390x.zig
@@ -174,35 +174,21 @@ pub fn clone() callconv(.naked) u64 {
 }
 
 pub fn restore() callconv(.naked) noreturn {
-    switch (builtin.zig_backend) {
-        .stage2_c => asm volatile (
-            \\lghi %%r1, %[number]
-            \\svc 0
-            :
-            : [number] "K" (@backingInt(SYS.sigreturn)),
-        ),
-        else => asm volatile (
-            \\svc 0
-            :
-            : [number] "{r1}" (@backingInt(SYS.sigreturn)),
-        ),
-    }
+    asm volatile (
+        \\lghi %%r1, %[number]
+        \\svc 0
+        :
+        : [number] "K" (@backingInt(SYS.sigreturn)),
+    );
 }
 
 pub fn restore_rt() callconv(.naked) noreturn {
-    switch (builtin.zig_backend) {
-        .stage2_c => asm volatile (
-            \\lghi %%r1, %[number]
-            \\svc 0
-            :
-            : [number] "K" (@backingInt(SYS.rt_sigreturn)),
-        ),
-        else => asm volatile (
-            \\svc 0
-            :
-            : [number] "{r1}" (@backingInt(SYS.rt_sigreturn)),
-        ),
-    }
+    asm volatile (
+        \\lghi %%r1, %[number]
+        \\svc 0
+        :
+        : [number] "K" (@backingInt(SYS.rt_sigreturn)),
+    );
 }
 
 pub const time_t = i64;
diff --git a/lib/std/os/linux/x32.zig b/lib/std/os/linux/x32.zig
index 429aac82973def7599ecc441d35409d085e9b28f..19509018dd88783047346930ddff37d8b05887df 100644
--- a/lib/std/os/linux/x32.zig
+++ b/lib/std/os/linux/x32.zig
@@ -160,19 +160,12 @@ pub fn clone() callconv(.naked) u32 {
 pub const restore = restore_rt;
 
 pub fn restore_rt() callconv(.naked) noreturn {
-    switch (builtin.zig_backend) {
-        .stage2_c => asm volatile (
-            \\ movl %[number], %%eax
-            \\ syscall
-            :
-            : [number] "i" (@backingInt(SYS.rt_sigreturn)),
-        ),
-        else => asm volatile (
-            \\ syscall
-            :
-            : [number] "{rax}" (@backingInt(SYS.rt_sigreturn)),
-        ),
-    }
+    asm volatile (
+        \\ movl %[number], %%eax
+        \\ syscall
+        :
+        : [number] "i" (@backingInt(SYS.rt_sigreturn)),
+    );
 }
 
 pub const time_t = i64;
diff --git a/lib/std/os/linux/x86.zig b/lib/std/os/linux/x86.zig
index 8145bf2826c780bcd0e5b85de341b6dc7d6b1281..4a1c593c121939fb58e4ce33cf1d9b2a11f260a2 100644
--- a/lib/std/os/linux/x86.zig
+++ b/lib/std/os/linux/x86.zig
@@ -186,37 +186,22 @@ pub fn clone() callconv(.naked) u32 {
 }
 
 pub fn restore() callconv(.naked) noreturn {
-    switch (builtin.zig_backend) {
-        .stage2_c => asm volatile (
-            \\ addl $4, %%esp
-            \\ movl %[number], %%eax
-            \\ int $0x80
-            :
-            : [number] "i" (@backingInt(SYS.sigreturn)),
-        ),
-        else => asm volatile (
-            \\ addl $4, %%esp
-            \\ int $0x80
-            :
-            : [number] "{eax}" (@backingInt(SYS.sigreturn)),
-        ),
-    }
+    asm volatile (
+        \\ addl $4, %%esp
+        \\ movl %[number], %%eax
+        \\ int $0x80
+        :
+        : [number] "i" (@backingInt(SYS.sigreturn)),
+    );
 }
 
 pub fn restore_rt() callconv(.naked) noreturn {
-    switch (builtin.zig_backend) {
-        .stage2_c => asm volatile (
-            \\ movl %[number], %%eax
-            \\ int $0x80
-            :
-            : [number] "i" (@backingInt(SYS.rt_sigreturn)),
-        ),
-        else => asm volatile (
-            \\ int $0x80
-            :
-            : [number] "{eax}" (@backingInt(SYS.rt_sigreturn)),
-        ),
-    }
+    asm volatile (
+        \\ movl %[number], %%eax
+        \\ int $0x80
+        :
+        : [number] "i" (@backingInt(SYS.rt_sigreturn)),
+    );
 }
 
 pub const VDSO = struct {
diff --git a/lib/std/os/linux/x86_64.zig b/lib/std/os/linux/x86_64.zig
index ae5808921c648f93130b26009940acc9376e97f9..465a330156554a035b258bcf682fab24cb4fe7ba 100644
--- a/lib/std/os/linux/x86_64.zig
+++ b/lib/std/os/linux/x86_64.zig
@@ -146,19 +146,12 @@ pub fn clone() callconv(.naked) u64 {
 pub const restore = restore_rt;
 
 pub fn restore_rt() callconv(.naked) noreturn {
-    switch (builtin.zig_backend) {
-        .stage2_c => asm volatile (
-            \\ movl %[number], %%eax
-            \\ syscall
-            :
-            : [number] "i" (@backingInt(SYS.rt_sigreturn)),
-        ),
-        else => asm volatile (
-            \\ syscall
-            :
-            : [number] "{rax}" (@backingInt(SYS.rt_sigreturn)),
-        ),
-    }
+    asm volatile (
+        \\ movl %[number], %%eax
+        \\ syscall
+        :
+        : [number] "i" (@backingInt(SYS.rt_sigreturn)),
+    );
 }
 
 pub const time_t = i64;
diff --git a/lib/std/os/linux/xtensa.zig b/lib/std/os/linux/xtensa.zig
index 839df53cace5d533c35bb986bcc08bcba8b5dd0c..0bda5a9331365dea6c333818b1624cbfd7aba444 100644
--- a/lib/std/os/linux/xtensa.zig
+++ b/lib/std/os/linux/xtensa.zig
@@ -173,19 +173,12 @@ pub fn clone() callconv(.naked) u32 {
 pub const restore = restore_rt;
 
 pub fn restore_rt() callconv(.naked) noreturn {
-    switch (builtin.zig_backend) {
-        .stage2_c => asm volatile (
-            \\ movi a2, %[number]
-            \\ syscall
-            :
-            : [number] "I" (@backingInt(SYS.rt_sigreturn)),
-        ),
-        else => asm volatile (
-            \\ syscall
-            :
-            : [number] "{a2}" (@backingInt(SYS.rt_sigreturn)),
-        ),
-    }
+    asm volatile (
+        \\ movi a2, %[number]
+        \\ syscall
+        :
+        : [number] "I" (@backingInt(SYS.rt_sigreturn)),
+    );
 }
 
 pub const VDSO = void;