diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp
--- a/clang/lib/Sema/SemaDecl.cpp
+++ b/clang/lib/Sema/SemaDecl.cpp
@@ -14493,7 +14493,7 @@
   FunctionScopeInfo *FSI = getCurFunction();
   FunctionDecl *FD = dcl ? dcl->getAsFunction() : nullptr;
 
-  if (FSI->UsesFPIntrin && !FD->hasAttr<StrictFPAttr>())
+  if (FSI->UsesFPIntrin && FD && !FD->hasAttr<StrictFPAttr>())
     FD->addAttr(StrictFPAttr::CreateImplicit(Context));
 
   sema::AnalysisBasedWarnings::Policy WP = AnalysisWarnings.getDefaultPolicy();
diff --git a/clang/test/SemaCXX/rounding-math-crash.cpp b/clang/test/SemaCXX/rounding-math-crash.cpp
new file mode 100644
--- /dev/null
+++ b/clang/test/SemaCXX/rounding-math-crash.cpp
@@ -0,0 +1,3 @@
+// RUN: %clang_cc1 -fsyntax-only -frounding-math -verify %s
+
+template <class b> b::a() {}  // expected-error {{nested name specifier}}