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
@@ -378,6 +378,16 @@
 #----------------------------------------------------------------------
 # C++ standard library options
 #----------------------------------------------------------------------
+ifneq ($(and $(USE_LIBSTDCPP), $(USE_LIBCPP)),)
+	$(error Libcxx and Libstdc++ cannot be used together)
+endif
+
+ifeq (1, $(USE_SYSTEM_STDLIB))
+	ifneq ($(or $(USE_LIBSTDCPP), $(USE_LIBCPP)),)
+		$(error Cannot use system's library and a custom library together)
+	endif
+endif
+
 ifeq (1,$(USE_LIBSTDCPP))
 	# Clang requires an extra flag: -stdlib=libstdc++
 	ifneq (,$(findstring clang,$(CC)))
@@ -406,6 +416,15 @@
 	endif
 endif
 
+# If no explicit request was made, but we have paths to a custom libcxx, use
+# them.
+ifeq ($(or $(USE_LIBSTDCPP), $(USE_LIBCPP), $(USE_SYSTEM_STDLIB)),)
+	ifneq ($(and $(LIBCPP_INCLUDE_DIR), $(LIBCPP_LIBRARY_DIR)),)
+		CXXFLAGS += -nostdlib++ -nostdinc++ -cxx-isystem $(LIBCPP_INCLUDE_DIR)
+		LDFLAGS += -L$(LLVM_LIBS_DIR) -Wl,-rpath,$(LIBCPP_LIBRARY_DIR) -lc++
+	endif
+endif
+
 #----------------------------------------------------------------------
 # Additional system libraries
 #----------------------------------------------------------------------
diff --git a/lldb/test/API/lang/objc/exceptions/Makefile b/lldb/test/API/lang/objc/exceptions/Makefile
--- a/lldb/test/API/lang/objc/exceptions/Makefile
+++ b/lldb/test/API/lang/objc/exceptions/Makefile
@@ -2,7 +2,7 @@
 
 CFLAGS_EXTRAS := -w
 
-
+USE_SYSTEM_STDLIB := 1
 
 LD_EXTRAS := -framework Foundation
 include Makefile.rules
diff --git a/lldb/test/API/macosx/macCatalyst/Makefile b/lldb/test/API/macosx/macCatalyst/Makefile
--- a/lldb/test/API/macosx/macCatalyst/Makefile
+++ b/lldb/test/API/macosx/macCatalyst/Makefile
@@ -3,6 +3,8 @@
 override TRIPLE := $(ARCH)-apple-ios13.1-macabi
 CFLAGS_EXTRAS := -target $(TRIPLE)
 
+USE_SYSTEM_STDLIB := 1
+
 # FIXME: rdar://problem/54986190
 # There is a Clang driver change missing on llvm.org.
 override CC=xcrun clang
diff --git a/lldb/test/API/tools/lldb-server/Makefile b/lldb/test/API/tools/lldb-server/Makefile
--- a/lldb/test/API/tools/lldb-server/Makefile
+++ b/lldb/test/API/tools/lldb-server/Makefile
@@ -2,5 +2,6 @@
 ENABLE_THREADS := YES
 CXX_SOURCES := main.cpp
 MAKE_DSYM :=NO
+USE_SYSTEM_STDLIB := 1
 
 include Makefile.rules