diff --git a/clang/include/clang/Driver/Options.td b/clang/include/clang/Driver/Options.td
--- a/clang/include/clang/Driver/Options.td
+++ b/clang/include/clang/Driver/Options.td
@@ -1579,6 +1579,7 @@
   HelpText<"Enable support for ignoring exception handling constructs">,
   MarshallingInfoFlag<LangOpts<"IgnoreExceptions">>;
 def fexcess_precision_EQ : Joined<["-"], "fexcess-precision=">, Group<f_Group>,
+  Flags<[CoreOption]>,
   HelpText<"Allows control over excess precision on targets where native "
   "support for the precision types is not available. By default, excess "
   "precision is used to calculate intermediate results following the "
diff --git a/clang/test/Driver/fexcess-precision.c b/clang/test/Driver/fexcess-precision.c
--- a/clang/test/Driver/fexcess-precision.c
+++ b/clang/test/Driver/fexcess-precision.c
@@ -1,29 +1,65 @@
+// Note: %s must be preceded by --, otherwise it may be interpreted as a
+// command-line option, e.g. on Mac where %s is commonly under /Users.
+
 // RUN: %clang -### -target i386 -fexcess-precision=fast -c %s 2>&1  \
 // RUN:   | FileCheck --check-prefix=CHECK-FAST %s
+// RUN: %clang_cl -### -target i386 -fexcess-precision=fast -c -- %s 2>&1 \
+// RUN:   | FileCheck --check-prefix=CHECK-FAST %s
+
 // RUN: %clang -### -target i386 -fexcess-precision=standard -c %s 2>&1  \
 // RUN:   | FileCheck --check-prefix=CHECK-STD %s
+// RUN: %clang_cl -### -target i386 -fexcess-precision=standard -c -- %s 2>&1 \
+// RUN:   | FileCheck --check-prefix=CHECK-STD %s
+
 // RUN: %clang -### -target i386 -fexcess-precision=16 -c %s 2>&1  \
 // RUN:   | FileCheck --check-prefix=CHECK-NONE %s
+// RUN: %clang_cl -### -target i386 -fexcess-precision=16 -c -- %s 2>&1 \
+// RUN:   | FileCheck --check-prefix=CHECK-NONE %s
+
 // RUN: %clang -### -target i386 -fexcess-precision=none -c %s 2>&1  \
 // RUN:   | FileCheck --check-prefix=CHECK-ERR-NONE %s
+// RUN: %clang_cl -### -target i386 -fexcess-precision=none -c -- %s 2>&1 \
+// RUN:   | FileCheck --check-prefix=CHECK-ERR-NONE %s
 
 // RUN: %clang -### -target x86_64 -fexcess-precision=fast -c %s 2>&1 \
 // RUN:   | FileCheck --check-prefix=CHECK-FAST %s
+// RUN: %clang_cl -### -target x86_64 -fexcess-precision=fast -c -- %s 2>&1 \
+// RUN:   | FileCheck --check-prefix=CHECK-FAST %s
+
 // RUN: %clang -### -target x86_64 -fexcess-precision=standard -c %s 2>&1 \
 // RUN:   | FileCheck --check-prefix=CHECK-STD %s
+// RUN: %clang_cl -### -target x86_64 -fexcess-precision=standard -c \
+// RUN: -- %s 2>&1 | FileCheck --check-prefix=CHECK-STD %s
+
 // RUN: %clang -### -target x86_64 -fexcess-precision=16 -c %s 2>&1 \
 // RUN:   | FileCheck --check-prefix=CHECK-NONE %s
+// RUN: %clang_cl -### -target x86_64 -fexcess-precision=16 -c -- %s 2>&1 \
+// RUN:   | FileCheck --check-prefix=CHECK-NONE %s
+
 // RUN: %clang -### -target x86_64 -fexcess-precision=none -c %s 2>&1 \
 // RUN:   | FileCheck --check-prefixes=CHECK-ERR-NONE %s
+// RUN: %clang_cl -### -target x86_64 -fexcess-precision=none -c -- %s 2>&1 \
+// RUN:   | FileCheck --check-prefixes=CHECK-ERR-NONE %s
 
 // RUN: %clang -### -target aarch64 -fexcess-precision=fast -c %s 2>&1 \
 // RUN:   | FileCheck --check-prefix=CHECK %s
+// RUN: %clang_cl -### -target aarch64 -fexcess-precision=fast -c -- %s 2>&1 \
+// RUN:   | FileCheck --check-prefix=CHECK %s
+
 // RUN: %clang -### -target aarch64 -fexcess-precision=standard -c %s 2>&1 \
 // RUN:   | FileCheck --check-prefix=CHECK %s
+// RUN: %clang_cl -### -target aarch64 -fexcess-precision=standard -c \
+// RUN: -- %s 2>&1 | FileCheck --check-prefix=CHECK %s
+
 // RUN: %clang -### -target aarch64 -fexcess-precision=16 -c %s 2>&1 \
 // RUN:   | FileCheck --check-prefix=CHECK-ERR-16 %s
+// RUN: %clang_cl -### -target aarch64 -fexcess-precision=16 -c -- %s 2>&1 \
+// RUN:   | FileCheck --check-prefix=CHECK-ERR-16 %s
+
 // RUN: %clang -### -target aarch64 -fexcess-precision=none -c %s 2>&1 \
 // RUN:   | FileCheck --check-prefix=CHECK-ERR-NONE %s
+// RUN: %clang_cl -### -target aarch64 -fexcess-precision=none -c -- %s 2>&1 \
+// RUN:   | FileCheck --check-prefix=CHECK-ERR-NONE %s
 
 // CHECK-FAST: "-ffloat16-excess-precision=fast"
 // CHECK-STD: "-ffloat16-excess-precision=standard"