diff --git a/tests/assembly/asm/aarch64-modifiers.rs b/tests/assembly/asm/aarch64-modifiers.rs
index b7ef1d77ea023..a4a41dd96c169 100644
--- a/tests/assembly/asm/aarch64-modifiers.rs
+++ b/tests/assembly/asm/aarch64-modifiers.rs
@@ -1,6 +1,7 @@
 //@ assembly-output: emit-asm
 //@ compile-flags: -O -C panic=abort
 //@ compile-flags: --target aarch64-unknown-linux-gnu
+//@ compile-flags: -Zmerge-functions=disabled
 //@ needs-llvm-components: aarch64
 
 #![feature(no_core, lang_items, rustc_attrs)]
@@ -29,12 +30,6 @@ macro_rules! check {
         // -O and extern "C" guarantee that the selected register is always r0/s0/d0/q0
         #[no_mangle]
         pub unsafe extern "C" fn $func() -> i32 {
-            // Hack to avoid function merging
-            extern "Rust" {
-                fn dont_merge(s: &str);
-            }
-            dont_merge(stringify!($func));
-
             let y;
             asm!($code, out($reg) y);
             y
diff --git a/tests/assembly/asm/aarch64-types.rs b/tests/assembly/asm/aarch64-types.rs
index f36345670e329..cf1882ba1a22e 100644
--- a/tests/assembly/asm/aarch64-types.rs
+++ b/tests/assembly/asm/aarch64-types.rs
@@ -4,6 +4,7 @@
 //@ [aarch64] needs-llvm-components: aarch64
 //@ [arm64ec] compile-flags: --target arm64ec-pc-windows-msvc
 //@ [arm64ec] needs-llvm-components: aarch64
+//@ compile-flags: -Zmerge-functions=disabled
 
 #![feature(no_core, lang_items, rustc_attrs, repr_simd, asm_experimental_arch, f16, f128)]
 #![crate_type = "rlib"]
@@ -132,12 +133,6 @@ macro_rules! check {
         // LLVM issue: <https://github.com/llvm/llvm-project/issues/94434>
         #[no_mangle]
         pub unsafe fn $func(inp: &$ty, out: &mut $ty) {
-            // Hack to avoid function merging
-            extern "Rust" {
-                fn dont_merge(s: &str);
-            }
-            dont_merge(stringify!($func));
-
             let x = *inp;
             let y;
             asm!(
@@ -155,12 +150,6 @@ macro_rules! check_reg {
         // FIXME(f16_f128): See FIXME in `check!`
         #[no_mangle]
         pub unsafe fn $func(inp: &$ty, out: &mut $ty) {
-            // Hack to avoid function merging
-            extern "Rust" {
-                fn dont_merge(s: &str);
-            }
-            dont_merge(stringify!($func));
-
             let x = *inp;
             let y;
             asm!(concat!($mov, " ", $reg, ", ", $reg), lateout($reg) y, in($reg) x);
diff --git a/tests/assembly/asm/arm-modifiers.rs b/tests/assembly/asm/arm-modifiers.rs
index 0674e169d72e6..d421e0e6954cc 100644
--- a/tests/assembly/asm/arm-modifiers.rs
+++ b/tests/assembly/asm/arm-modifiers.rs
@@ -2,6 +2,7 @@
 //@ compile-flags: -O -C panic=abort
 //@ compile-flags: --target armv7-unknown-linux-gnueabihf
 //@ compile-flags: -C target-feature=+neon
+//@ compile-flags: -Zmerge-functions=disabled
 //@ needs-llvm-components: arm
 
 #![feature(no_core, lang_items, rustc_attrs, repr_simd)]
@@ -40,12 +41,6 @@ macro_rules! check {
         // -O and extern "C" guarantee that the selected register is always r0/s0/d0/q0
         #[no_mangle]
         pub unsafe extern "C" fn $func() -> $ty {
-            // Hack to avoid function merging
-            extern "Rust" {
-                fn dont_merge(s: &str);
-            }
-            dont_merge(stringify!($func));
-
             let y;
             asm!(concat!($mov, " {0:", $modifier, "}, {0:", $modifier, "}"), out($reg) y);
             y
diff --git a/tests/assembly/asm/arm-types.rs b/tests/assembly/asm/arm-types.rs
index eeff1a070b492..448b92aa8399a 100644
--- a/tests/assembly/asm/arm-types.rs
+++ b/tests/assembly/asm/arm-types.rs
@@ -2,6 +2,7 @@
 //@ assembly-output: emit-asm
 //@ compile-flags: --target armv7-unknown-linux-gnueabihf
 //@ compile-flags: -C opt-level=0
+//@ compile-flags: -Zmerge-functions=disabled
 //@[d32] compile-flags: -C target-feature=+d32
 //@[neon] compile-flags: -C target-feature=+neon --cfg d32
 //@[neon] filecheck-flags: --check-prefix d32
@@ -114,12 +115,6 @@ macro_rules! check {
     ($func:ident $ty:ident $class:ident $mov:literal) => {
         #[no_mangle]
         pub unsafe fn $func(x: $ty) -> $ty {
-            // Hack to avoid function merging
-            extern "Rust" {
-                fn dont_merge(s: &str);
-            }
-            dont_merge(stringify!($func));
-
             let y;
             asm!(concat!($mov, " {}, {}"), out($class) y, in($class) x);
             y
@@ -131,12 +126,6 @@ macro_rules! check_reg {
     ($func:ident $ty:ident $reg:tt $mov:literal) => {
         #[no_mangle]
         pub unsafe fn $func(x: $ty) -> $ty {
-            // Hack to avoid function merging
-            extern "Rust" {
-                fn dont_merge(s: &str);
-            }
-            dont_merge(stringify!($func));
-
             let y;
             asm!(concat!($mov, " ", $reg, ", ", $reg), lateout($reg) y, in($reg) x);
             y
diff --git a/tests/assembly/asm/hexagon-types.rs b/tests/assembly/asm/hexagon-types.rs
index 269c7582a1cee..9389fcf9cbac9 100644
--- a/tests/assembly/asm/hexagon-types.rs
+++ b/tests/assembly/asm/hexagon-types.rs
@@ -1,5 +1,6 @@
 //@ assembly-output: emit-asm
 //@ compile-flags: --target hexagon-unknown-linux-musl
+//@ compile-flags: -Zmerge-functions=disabled
 //@ needs-llvm-components: hexagon
 
 #![feature(no_core, lang_items, rustc_attrs, repr_simd, asm_experimental_arch)]
@@ -41,12 +42,6 @@ macro_rules! check {
     ($func:ident $ty:ident $class:ident) => {
         #[no_mangle]
         pub unsafe fn $func(x: $ty) -> $ty {
-            // Hack to avoid function merging
-            extern "Rust" {
-                fn dont_merge(s: &str);
-            }
-            dont_merge(stringify!($func));
-
             let y;
             asm!("{} = {}", out($class) y, in($class) x);
             y
@@ -58,12 +53,6 @@ macro_rules! check_reg {
     ($func:ident $ty:ident $reg:tt) => {
         #[no_mangle]
         pub unsafe fn $func(x: $ty) -> $ty {
-            // Hack to avoid function merging
-            extern "Rust" {
-                fn dont_merge(s: &str);
-            }
-            dont_merge(stringify!($func));
-
             let y;
             asm!(concat!($reg, " = ", $reg), lateout($reg) y, in($reg) x);
             y
@@ -77,12 +66,6 @@ macro_rules! check_reg {
 // CHECK: InlineAsm End
 #[no_mangle]
 pub unsafe fn sym_static() {
-    // Hack to avoid function merging
-    extern "Rust" {
-        fn dont_merge(s: &str);
-    }
-    dont_merge(stringify!($func));
-
     asm!("r0 = #{}", sym extern_static);
 }
 
@@ -92,12 +75,6 @@ pub unsafe fn sym_static() {
 // CHECK: InlineAsm End
 #[no_mangle]
 pub unsafe fn sym_fn() {
-    // Hack to avoid function merging
-    extern "Rust" {
-        fn dont_merge(s: &str);
-    }
-    dont_merge(stringify!($func));
-
     asm!("r0 = #{}", sym extern_func);
 }
 
diff --git a/tests/assembly/asm/loongarch-type.rs b/tests/assembly/asm/loongarch-type.rs
index e4c46cfcf81b1..1b097f4110501 100644
--- a/tests/assembly/asm/loongarch-type.rs
+++ b/tests/assembly/asm/loongarch-type.rs
@@ -1,5 +1,6 @@
 //@ assembly-output: emit-asm
 //@ compile-flags: --target loongarch64-unknown-linux-gnu
+//@ compile-flags: -Zmerge-functions=disabled
 //@ needs-llvm-components: loongarch
 
 #![feature(no_core, lang_items, rustc_attrs, asm_experimental_arch)]
@@ -39,11 +40,6 @@ extern "C" {
     static extern_static: u8;
 }
 
-// Hack to avoid function merging
-extern "Rust" {
-    fn dont_merge(s: &str);
-}
-
 // CHECK-LABEL: sym_fn:
 // CHECK: #APP
 // CHECK: pcalau12i $t0, %got_pc_hi20(extern_func)
@@ -67,8 +63,6 @@ pub unsafe fn sym_static() {
 macro_rules! check { ($func:ident, $ty:ty, $class:ident, $mov:literal) => {
     #[no_mangle]
     pub unsafe fn $func(x: $ty) -> $ty {
-        dont_merge(stringify!($func));
-
         let y;
         asm!(concat!($mov," {}, {}"), out($class) y, in($class) x);
         y
@@ -78,8 +72,6 @@ macro_rules! check { ($func:ident, $ty:ty, $class:ident, $mov:literal) => {
 macro_rules! check_reg { ($func:ident, $ty:ty, $reg:tt, $mov:literal) => {
     #[no_mangle]
     pub unsafe fn $func(x: $ty) -> $ty {
-        dont_merge(stringify!($func));
-
         let y;
         asm!(concat!($mov, " ", $reg, ", ", $reg), lateout($reg) y, in($reg) x);
         y
diff --git a/tests/assembly/asm/mips-types.rs b/tests/assembly/asm/mips-types.rs
index bd62f4a5236c2..f40a28be4a7e1 100644
--- a/tests/assembly/asm/mips-types.rs
+++ b/tests/assembly/asm/mips-types.rs
@@ -4,6 +4,7 @@
 //@[mips32] needs-llvm-components: mips
 //@[mips64] compile-flags: --target mips64-unknown-linux-gnuabi64
 //@[mips64] needs-llvm-components: mips
+//@ compile-flags: -Zmerge-functions=disabled
 
 #![feature(no_core, lang_items, rustc_attrs, repr_simd, asm_experimental_arch)]
 #![crate_type = "rlib"]
@@ -43,16 +44,9 @@ extern "C" {
     static extern_static: u8;
 }
 
-// Hack to avoid function merging
-extern "Rust" {
-    fn dont_merge(s: &str);
-}
-
 macro_rules! check { ($func:ident, $ty:ty, $class:ident, $mov:literal) => {
     #[no_mangle]
     pub unsafe fn $func(x: $ty) -> $ty {
-        dont_merge(stringify!($func));
-
         let y;
         asm!(concat!($mov," {}, {}"), out($class) y, in($class) x);
         y
@@ -62,8 +56,6 @@ macro_rules! check { ($func:ident, $ty:ty, $class:ident, $mov:literal) => {
 macro_rules! check_reg { ($func:ident, $ty:ty, $reg:tt, $mov:literal) => {
     #[no_mangle]
     pub unsafe fn $func(x: $ty) -> $ty {
-        dont_merge(stringify!($func));
-
         let y;
         asm!(concat!($mov, " ", $reg, ", ", $reg), lateout($reg) y, in($reg) x);
         y
diff --git a/tests/assembly/asm/powerpc-types.rs b/tests/assembly/asm/powerpc-types.rs
index bc8af08ad1133..85321e5f345ad 100644
--- a/tests/assembly/asm/powerpc-types.rs
+++ b/tests/assembly/asm/powerpc-types.rs
@@ -4,6 +4,7 @@
 //@[powerpc] needs-llvm-components: powerpc
 //@[powerpc64] compile-flags: --target powerpc64-unknown-linux-gnu
 //@[powerpc64] needs-llvm-components: powerpc
+//@ compile-flags: -Zmerge-functions=disabled
 
 #![feature(no_core, lang_items, rustc_attrs, repr_simd, asm_experimental_arch)]
 #![crate_type = "rlib"]
@@ -43,16 +44,9 @@ extern "C" {
     static extern_static: u8;
 }
 
-// Hack to avoid function merging
-extern "Rust" {
-    fn dont_merge(s: &str);
-}
-
 macro_rules! check { ($func:ident, $ty:ty, $class:ident, $mov:literal) => {
     #[no_mangle]
     pub unsafe fn $func(x: $ty) -> $ty {
-        dont_merge(stringify!($func));
-
         let y;
         asm!(concat!($mov," {}, {}"), out($class) y, in($class) x);
         y
@@ -62,8 +56,6 @@ macro_rules! check { ($func:ident, $ty:ty, $class:ident, $mov:literal) => {
 macro_rules! check_reg { ($func:ident, $ty:ty, $rego:tt, $regc:tt, $mov:literal) => {
     #[no_mangle]
     pub unsafe fn $func(x: $ty) -> $ty {
-        dont_merge(stringify!($func));
-
         let y;
         asm!(concat!($mov, " ", $rego, ", ", $rego), lateout($regc) y, in($regc) x);
         y
diff --git a/tests/assembly/asm/riscv-types.rs b/tests/assembly/asm/riscv-types.rs
index 51b3aaf99d944..1f5d7d85b0ad9 100644
--- a/tests/assembly/asm/riscv-types.rs
+++ b/tests/assembly/asm/riscv-types.rs
@@ -27,6 +27,7 @@
 //@[riscv32-zfh] filecheck-flags: --check-prefix zfhmin
 
 //@ compile-flags: -C target-feature=+d
+//@ compile-flags: -Zmerge-functions=disabled
 
 #![feature(no_core, lang_items, rustc_attrs, f16)]
 #![crate_type = "rlib"]
@@ -90,12 +91,6 @@ macro_rules! check {
     ($func:ident $ty:ident $class:ident $mov:literal) => {
         #[no_mangle]
         pub unsafe fn $func(x: $ty) -> $ty {
-            // Hack to avoid function merging
-            extern "Rust" {
-                fn dont_merge(s: &str);
-            }
-            dont_merge(stringify!($func));
-
             let y;
             asm!(concat!($mov, " {}, {}"), out($class) y, in($class) x);
             y
@@ -107,12 +102,6 @@ macro_rules! check_reg {
     ($func:ident $ty:ident $reg:tt $mov:literal) => {
         #[no_mangle]
         pub unsafe fn $func(x: $ty) -> $ty {
-            // Hack to avoid function merging
-            extern "Rust" {
-                fn dont_merge(s: &str);
-            }
-            dont_merge(stringify!($func));
-
             let y;
             asm!(concat!($mov, " ", $reg, ", ", $reg), lateout($reg) y, in($reg) x);
             y
diff --git a/tests/assembly/asm/s390x-types.rs b/tests/assembly/asm/s390x-types.rs
index 661907360bd28..e68b18d7aa690 100644
--- a/tests/assembly/asm/s390x-types.rs
+++ b/tests/assembly/asm/s390x-types.rs
@@ -2,6 +2,7 @@
 //@ assembly-output: emit-asm
 //@[s390x] compile-flags: --target s390x-unknown-linux-gnu
 //@[s390x] needs-llvm-components: systemz
+//@ compile-flags: -Zmerge-functions=disabled
 
 #![feature(no_core, lang_items, rustc_attrs, repr_simd, asm_experimental_arch)]
 #![crate_type = "rlib"]
@@ -42,16 +43,9 @@ extern "C" {
     static extern_static: u8;
 }
 
-// Hack to avoid function merging
-extern "Rust" {
-    fn dont_merge(s: &str);
-}
-
 macro_rules! check { ($func:ident, $ty:ty, $class:ident, $mov:literal) => {
     #[no_mangle]
     pub unsafe fn $func(x: $ty) -> $ty {
-        dont_merge(stringify!($func));
-
         let y;
         asm!(concat!($mov," {}, {}"), out($class) y, in($class) x);
         y
@@ -61,8 +55,6 @@ macro_rules! check { ($func:ident, $ty:ty, $class:ident, $mov:literal) => {
 macro_rules! check_reg { ($func:ident, $ty:ty, $reg:tt, $mov:literal) => {
     #[no_mangle]
     pub unsafe fn $func(x: $ty) -> $ty {
-        dont_merge(stringify!($func));
-
         let y;
         asm!(concat!($mov, " %", $reg, ", %", $reg), lateout($reg) y, in($reg) x);
         y
diff --git a/tests/assembly/asm/x86-modifiers.rs b/tests/assembly/asm/x86-modifiers.rs
index c5e393b10564e..5a48af9205f75 100644
--- a/tests/assembly/asm/x86-modifiers.rs
+++ b/tests/assembly/asm/x86-modifiers.rs
@@ -7,6 +7,7 @@
 //@[i686] needs-llvm-components: x86
 //@ compile-flags: -C llvm-args=--x86-asm-syntax=intel
 //@ compile-flags: -C target-feature=+avx512bw
+//@ compile-flags: -Zmerge-functions=disabled
 
 #![feature(no_core, lang_items, rustc_attrs)]
 #![crate_type = "rlib"]
@@ -38,12 +39,6 @@ macro_rules! check {
         // -O and extern "C" guarantee that the selected register is always ax/xmm0
         #[no_mangle]
         pub unsafe extern "C" fn $func() -> i32 {
-            // Hack to avoid function merging
-            extern "Rust" {
-                fn dont_merge(s: &str);
-            }
-            dont_merge(stringify!($func));
-
             let y;
             asm!(concat!($mov, " {0:", $modifier, "}, {0:", $modifier, "}"), out($reg) y);
             y
diff --git a/tests/assembly/asm/x86-types.rs b/tests/assembly/asm/x86-types.rs
index 8e229614420b6..a40bc10d9915c 100644
--- a/tests/assembly/asm/x86-types.rs
+++ b/tests/assembly/asm/x86-types.rs
@@ -6,6 +6,7 @@
 //@[i686] needs-llvm-components: x86
 //@ compile-flags: -C llvm-args=--x86-asm-syntax=intel
 //@ compile-flags: -C target-feature=+avx512bw
+//@ compile-flags: -Zmerge-functions=disabled
 
 #![feature(no_core, lang_items, rustc_attrs, repr_simd, f16, f128)]
 #![crate_type = "rlib"]
@@ -283,12 +284,6 @@ macro_rules! check {
     ($func:ident $ty:ident $class:ident $mov:literal) => {
         #[no_mangle]
         pub unsafe fn $func(x: $ty) -> $ty {
-            // Hack to avoid function merging
-            extern "Rust" {
-                fn dont_merge(s: &str);
-            }
-            dont_merge(stringify!($func));
-
             let y;
             asm!(concat!($mov, " {}, {}"), lateout($class) y, in($class) x);
             y
@@ -300,12 +295,6 @@ macro_rules! check_reg {
     ($func:ident $ty:ident $reg:tt $mov:literal) => {
         #[no_mangle]
         pub unsafe fn $func(x: $ty) -> $ty {
-            // Hack to avoid function merging
-            extern "Rust" {
-                fn dont_merge(s: &str);
-            }
-            dont_merge(stringify!($func));
-
             let y;
             asm!(concat!($mov, " ", $reg, ", ", $reg), lateout($reg) y, in($reg) x);
             y