1 files changed, 150 insertions, 0 deletions
diff --git a/src/tools/rustfmt/tests/source/cfg_if/detect/error_macros.rs b/src/tools/rustfmt/tests/source/cfg_if/detect/error_macros.rs
new file mode 100644
index 000000000..6769757ed
--- /dev/null
+++ b/src/tools/rustfmt/tests/source/cfg_if/detect/error_macros.rs
@@ -0,0 +1,150 @@
+//! The `is_{target_arch}_feature_detected!` macro are only available on their
+//! architecture. These macros provide a better error messages when the user
+//! attempts to call them in a different architecture.
+
+/// Prevents compilation if `is_x86_feature_detected` is used somewhere
+/// else than `x86` and `x86_64` targets.
+#[cfg(not(any(target_arch = "x86", target_arch = "x86_64")))]
+#[macro_export]
+#[unstable(feature = "stdsimd", issue = "27731")]
+macro_rules! is_x86_feature_detected {
+    ($t: tt) => {
+        compile_error!(
+            r#"
+        is_x86_feature_detected can only be used on x86 and x86_64 targets.
+        You can prevent it from being used in other architectures by
+        guarding it behind a cfg(target_arch) as follows:
+
+            #[cfg(any(target_arch = "x86", target_arch = "x86_64"))] {
+                if is_x86_feature_detected(...) { ... }
+            }
+        "#
+        )
+    };
+}
+
+/// Prevents compilation if `is_arm_feature_detected` is used somewhere else
+/// than `ARM` targets.
+#[cfg(not(target_arch = "arm"))]
+#[macro_export]
+#[unstable(feature = "stdsimd", issue = "27731")]
+macro_rules! is_arm_feature_detected {
+    ($t:tt) => {
+        compile_error!(
+            r#"
+        is_arm_feature_detected can only be used on ARM targets.
+        You can prevent it from being used in other architectures by
+        guarding it behind a cfg(target_arch) as follows:
+
+            #[cfg(target_arch = "arm")] {
+                if is_arm_feature_detected(...) { ... }
+            }
+        "#
+        )
+    };
+}
+
+/// Prevents compilation if `is_aarch64_feature_detected` is used somewhere else
+/// than `aarch64` targets.
+#[cfg(not(target_arch = "aarch64"))]
+#[macro_export]
+#[unstable(feature = "stdsimd", issue = "27731")]
+macro_rules! is_aarch64_feature_detected {
+    ($t: tt) => {
+        compile_error!(
+            r#"
+        is_aarch64_feature_detected can only be used on AArch64 targets.
+        You can prevent it from being used in other architectures by
+        guarding it behind a cfg(target_arch) as follows:
+
+            #[cfg(target_arch = "aarch64")] {
+                if is_aarch64_feature_detected(...) { ... }
+            }
+        "#
+        )
+    };
+}
+
+/// Prevents compilation if `is_powerpc_feature_detected` is used somewhere else
+/// than `PowerPC` targets.
+#[cfg(not(target_arch = "powerpc"))]
+#[macro_export]
+#[unstable(feature = "stdsimd", issue = "27731")]
+macro_rules! is_powerpc_feature_detected {
+    ($t:tt) => {
+        compile_error!(
+            r#"
+is_powerpc_feature_detected can only be used on PowerPC targets.
+You can prevent it from being used in other architectures by
+guarding it behind a cfg(target_arch) as follows:
+
+    #[cfg(target_arch = "powerpc")] {
+        if is_powerpc_feature_detected(...) { ... }
+    }
+"#
+        )
+    };
+}
+
+/// Prevents compilation if `is_powerpc64_feature_detected` is used somewhere
+/// else than `PowerPC64` targets.
+#[cfg(not(target_arch = "powerpc64"))]
+#[macro_export]
+#[unstable(feature = "stdsimd", issue = "27731")]
+macro_rules! is_powerpc64_feature_detected {
+    ($t:tt) => {
+        compile_error!(
+            r#"
+is_powerpc64_feature_detected can only be used on PowerPC64 targets.
+You can prevent it from being used in other architectures by
+guarding it behind a cfg(target_arch) as follows:
+
+    #[cfg(target_arch = "powerpc64")] {
+        if is_powerpc64_feature_detected(...) { ... }
+    }
+"#
+        )
+    };
+}
+
+/// Prevents compilation if `is_mips_feature_detected` is used somewhere else
+/// than `MIPS` targets.
+#[cfg(not(target_arch = "mips"))]
+#[macro_export]
+#[unstable(feature = "stdsimd", issue = "27731")]
+macro_rules! is_mips_feature_detected {
+    ($t:tt) => {
+        compile_error!(
+            r#"
+        is_mips_feature_detected can only be used on MIPS targets.
+        You can prevent it from being used in other architectures by
+        guarding it behind a cfg(target_arch) as follows:
+
+            #[cfg(target_arch = "mips")] {
+                if is_mips_feature_detected(...) { ... }
+            }
+        "#
+        )
+    };
+}
+
+/// Prevents compilation if `is_mips64_feature_detected` is used somewhere else
+/// than `MIPS64` targets.
+#[cfg(not(target_arch = "mips64"))]
+#[macro_export]
+#[unstable(feature = "stdsimd", issue = "27731")]
+macro_rules! is_mips64_feature_detected {
+    ($t:tt) => {
+        compile_error!(
+            r#"
+        is_mips64_feature_detected can only be used on MIPS64 targets.
+        You can prevent it from being used in other architectures by
+        guarding it behind a cfg(target_arch) as follows:
+
+            #[cfg(target_arch = "mips64")] {
+                if is_mips64_feature_detected(...) { ... }
+            }
+        "#
+        )
+    };
+}