[Sema] Check if types are resolved before querying function description.

Author: Dinar Temirbulatov

clang/lib/Sema/SemaChecking.cpp

@@ -3507,11 +3507,15 @@ bool Sema::ParseSVEImmChecks(
 static ArmStreamingType getArmStreamingFnType(const FunctionDecl *FD) {
   if (FD->hasAttr<ArmLocallyStreamingAttr>())
     return ArmStreaming;
-  if (const auto *T = FD->getType()->getAs<FunctionProtoType>()) {
-    if (T->getAArch64SMEAttributes() & FunctionType::SME_PStateSMEnabledMask)
-      return ArmStreaming;
-    if (T->getAArch64SMEAttributes() & FunctionType::SME_PStateSMCompatibleMask)
-      return ArmStreamingCompatible;
+  if (const Type *Ty = FD->getType().getTypePtrOrNull()) {
+    if (const auto *FPT = Ty->getAs<FunctionProtoType>()) {
+      if (FPT->getAArch64SMEAttributes() &
+          FunctionType::SME_PStateSMEnabledMask)
+        return ArmStreaming;
+      if (FPT->getAArch64SMEAttributes() &
+          FunctionType::SME_PStateSMCompatibleMask)
+        return ArmStreamingCompatible;
+    }
   }
   return ArmNonStreaming;
 }

clang/test/SemaCXX/aarch64-sve-resolve-type.cpp

@@ -0,0 +1,23 @@
+// RUN: %clang_cc1 -triple aarch64-none-linux-gnu -target-feature +sve -fsyntax-only %s
+
+// REQUIRES: aarch64-registered-target || arm-registered-target
+
+// expected-no-diagnostics
+
+struct a {};
+__SVFloat32_t b(a);
+template <class c> using e = decltype(b(c()));
+e<a> f(a);
+template <class c> using h = decltype(f(c()));
+template <class g> struct i {
+  static void j() {
+    a d;
+    g()(d);
+  }
+};
+struct k {
+  template <class c> void operator()(c) {
+    [](h<c>) {};
+  }
+  void l() { i<k>::j; }
+};