Remove vararg support check

This check wasn't very useful and removing it simplifies the code.

Author: bjorn3

src/abi/mod.rs

@@ -140,18 +140,8 @@ pub(crate) fn get_function_sig<'tcx>(
     tcx: TyCtxt<'tcx>,
     triple: &target_lexicon::Triple,
     inst: Instance<'tcx>,
-    support_vararg: bool,
 ) -> Signature {
     assert!(!inst.substs.needs_infer());
-    let fn_sig = tcx
-        .normalize_erasing_late_bound_regions(ParamEnv::reveal_all(), fn_sig_for_fn_abi(tcx, inst));
-    if fn_sig.c_variadic && !support_vararg {
-        tcx.sess.span_fatal(
-            tcx.def_span(inst.def_id()),
-            "Variadic function definitions are not yet supported",
-        );
-    }
-
     clif_sig_from_fn_abi(
         tcx,
         triple,
@@ -166,7 +156,7 @@ pub(crate) fn import_function<'tcx>(
     inst: Instance<'tcx>,
 ) -> FuncId {
     let name = tcx.symbol_name(inst).name.to_string();
-    let sig = get_function_sig(tcx, module.isa().triple(), inst, true);
+    let sig = get_function_sig(tcx, module.isa().triple(), inst);
     module
         .declare_function(&name, Linkage::Import, &sig)
         .unwrap()

src/base.rs

@@ -22,7 +22,7 @@ pub(crate) fn codegen_fn<'tcx>(
 
     // Declare function
     let name = tcx.symbol_name(instance).name.to_string();
-    let sig = get_function_sig(tcx, cx.module.isa().triple(), instance, false);
+    let sig = get_function_sig(tcx, cx.module.isa().triple(), instance);
     let func_id = cx.module.declare_function(&name, linkage, &sig).unwrap();
 
     cx.cached_context.clear();

src/driver/jit.rs

@@ -157,7 +157,7 @@ extern "C" fn __clif_jit_fn(instance_ptr: *const Instance<'static>) -> *const u8
             let mut cx = crate::CodegenCx::new(tcx, jit_module, false, false);
 
             let name = tcx.symbol_name(instance).name.to_string();
-            let sig = crate::abi::get_function_sig(tcx, cx.module.isa().triple(), instance, true);
+            let sig = crate::abi::get_function_sig(tcx, cx.module.isa().triple(), instance);
             let func_id = cx
                 .module
                 .declare_function(&name, Linkage::Export, &sig)
@@ -243,7 +243,7 @@ pub(super) fn codegen_shim<'tcx>(cx: &mut CodegenCx<'tcx, impl Module>, inst: In
     let pointer_type = cx.module.target_config().pointer_type();
 
     let name = tcx.symbol_name(inst).name.to_string();
-    let sig = crate::abi::get_function_sig(tcx, cx.module.isa().triple(), inst, true);
+    let sig = crate::abi::get_function_sig(tcx, cx.module.isa().triple(), inst);
     let func_id = cx
         .module
         .declare_function(&name, Linkage::Export, &sig)

src/driver/mod.rs

@@ -51,12 +51,7 @@ fn predefine_mono_items<'tcx>(
             match mono_item {
                 MonoItem::Fn(instance) => {
                     let name = cx.tcx.symbol_name(instance).name.to_string();
-                    let sig= get_function_sig(
-                        cx.tcx,
-                        cx.module.isa().triple(),
-                        instance,
-                        false,
-                    );
+                    let sig = get_function_sig(cx.tcx, cx.module.isa().triple(), instance);
                     let linkage = crate::linkage::get_clif_linkage(mono_item, linkage, visibility);
                     cx.module.declare_function(&name, linkage, &sig).unwrap();
                 }

src/main_shim.rs

@@ -70,7 +70,7 @@ pub(crate) fn maybe_create_entry_wrapper(
         let instance = Instance::mono(tcx, rust_main_def_id).polymorphize(tcx);
 
         let main_name = tcx.symbol_name(instance).name.to_string();
-        let main_sig = get_function_sig(tcx, m.isa().triple(), instance, false);
+        let main_sig = get_function_sig(tcx, m.isa().triple(), instance);
         let main_func_id = m
             .declare_function(&main_name, Linkage::Import, &main_sig)
             .unwrap();