diff --git a/compiler/rustc_ast_lowering/src/asm.rs b/compiler/rustc_ast_lowering/src/asm.rs
index 87af7959a884d..65784af92c7ca 100644
--- a/compiler/rustc_ast_lowering/src/asm.rs
+++ b/compiler/rustc_ast_lowering/src/asm.rs
@@ -38,6 +38,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
         }
         if let Some(asm_arch) = asm_arch {
             // Inline assembly is currently only stable for these architectures.
+            // (See also compiletest's `has_asm_support`.)
             let is_stable = matches!(
                 asm_arch,
                 asm::InlineAsmArch::X86
diff --git a/src/tools/compiletest/src/common.rs b/src/tools/compiletest/src/common.rs
index 978836cb6636a..08d3c1c343e08 100644
--- a/src/tools/compiletest/src/common.rs
+++ b/src/tools/compiletest/src/common.rs
@@ -481,9 +481,17 @@ impl Config {
     }
 
     pub fn has_asm_support(&self) -> bool {
+        // This should match the stable list in `LoweringContext::lower_inline_asm`.
         static ASM_SUPPORTED_ARCHS: &[&str] = &[
-            "x86", "x86_64", "arm", "aarch64", "riscv32",
+            "x86",
+            "x86_64",
+            "arm",
+            "aarch64",
+            "arm64ec",
+            "riscv32",
             "riscv64",
+            "loongarch64",
+            "s390x",
             // These targets require an additional asm_experimental_arch feature.
             // "nvptx64", "hexagon", "mips", "mips64", "spirv", "wasm32",
         ];