mark some target features as 'forbidden' so they cannot be (un)set

For now, this is just a warning, but should become a hard error in the future

1 files changed, 5 insertions, 0 deletions

diff --git a/compiler/rustc_codegen_llvm/messages.ftl b/compiler/rustc_codegen_llvm/messages.ftl
index 0950e4bb26b..63c64269eb8 100644
--- a/compiler/rustc_codegen_llvm/messages.ftl
+++ b/compiler/rustc_codegen_llvm/messages.ftl
@@ -7,6 +7,11 @@ codegen_llvm_dynamic_linking_with_lto =
 
 codegen_llvm_fixed_x18_invalid_arch = the `-Zfixed-x18` flag is not supported on the `{$arch}` architecture
 
+codegen_llvm_forbidden_ctarget_feature =
+    target feature `{$feature}` cannot be toggled with `-Ctarget-feature`: {$reason}
+    .note = this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
+codegen_llvm_forbidden_ctarget_feature_issue = for more information, see issue #116344 <https://github.com/rust-lang/rust/issues/116344>
+
 codegen_llvm_from_llvm_diag = {$message}
 
 codegen_llvm_from_llvm_optimization_diag = {$filename}:{$line}:{$column} {$pass_name} ({$kind}): {$message}