diff --git a/lldb/packages/Python/lldbsuite/test/make/Makefile.rules b/lldb/packages/Python/lldbsuite/test/make/Makefile.rules
--- a/lldb/packages/Python/lldbsuite/test/make/Makefile.rules
+++ b/lldb/packages/Python/lldbsuite/test/make/Makefile.rules
@@ -458,11 +458,11 @@
 endif
 
 #----------------------------------------------------------------------
-# Check if we have a precompiled header
+# Check if we have a precompiled headers
 #----------------------------------------------------------------------
-ifneq "$(strip $(PCH_CXX_SOURCE))" ""
-	PCH_OUTPUT = $(PCH_CXX_SOURCE:.h=.h.pch)
-	PCHFLAGS = -include $(PCH_CXX_SOURCE)
+ifneq "$(strip $(PCH_CXX_SOURCES))" ""
+	PCH_OUTPUT = $(PCH_CXX_SOURCES:.h=.h.pch)
+	PCHFLAGS = $(addprefix -include-pch , $(PCH_OUTPUT))
 endif
 
 #----------------------------------------------------------------------
@@ -600,11 +600,11 @@
 endif
 
 #----------------------------------------------------------------------
-# Make the precompiled header and compile C++ sources against it
+# Make the precompiled headers and compile C++ sources against it
 #----------------------------------------------------------------------
 
 ifneq "$(PCH_OUTPUT)" ""
-$(PCH_OUTPUT) : $(PCH_CXX_SOURCE)
+$(PCH_OUTPUT) : $(PCH_CXX_SOURCES)
 	$(CXX) $(CXXFLAGS) -x c++-header -o $@ $<
 endif
 
diff --git a/lldb/test/API/lang/cpp/gmodules/basic/Makefile b/lldb/test/API/lang/cpp/gmodules/basic/Makefile
--- a/lldb/test/API/lang/cpp/gmodules/basic/Makefile
+++ b/lldb/test/API/lang/cpp/gmodules/basic/Makefile
@@ -1,4 +1,4 @@
-PCH_CXX_SOURCE = pch.h
+PCH_CXX_SOURCES = pch.h
 CXX_SOURCES = main.cpp
 CFLAGS_EXTRAS := $(MODULE_DEBUG_INFO_FLAGS)