support another Apple build environment

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@131996 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/Makefile b/Makefile
index 5a7118e..62d1bb3 100644
--- a/Makefile
+++ b/Makefile
@@ -9,6 +9,12 @@
 SYMROOT=.
 export TRIPLE=-apple-
 
+ifeq (,$(RC_INDIGO))
+	INSTALL_PREFIX=""
+else
+	INSTALL_PREFIX="$(SDKROOT)"
+endif
+
 installsrc:: $(SRCROOT)
 
 	ditto $(SRCDIRS)/include $(SRCROOT)/include
@@ -20,19 +26,19 @@
 
 installhdrs::
 
-	mkdir -p $(DSTROOT)/usr/include/c++/v1/ext
-	rsync -r --exclude=".*" $(SRCDIRS)/include/* $(DSTROOT)/usr/include/c++/v1/
-	chown -R root:wheel $(DSTROOT)/usr/include
-	chmod 755 $(DSTROOT)/usr/include/c++/v1
-	chmod 644 $(DSTROOT)/usr/include/c++/v1/*
-	chmod 755 $(DSTROOT)/usr/include/c++/v1/ext
-	chmod 644 $(DSTROOT)/usr/include/c++/v1/ext/*
+	mkdir -p $(DSTROOT)/$(INSTALL_PREFIX)/usr/include/c++/v1/ext
+	rsync -r --exclude=".*" $(SRCDIRS)/include/* $(DSTROOT)/$(INSTALL_PREFIX)/usr/include/c++/v1/
+	chown -R root:wheel $(DSTROOT)/$(INSTALL_PREFIX)/usr/include
+	chmod 755 $(DSTROOT)/$(INSTALL_PREFIX)/usr/include/c++/v1
+	chmod 644 $(DSTROOT)/$(INSTALL_PREFIX)/usr/include/c++/v1/*
+	chmod 755 $(DSTROOT)/$(INSTALL_PREFIX)/usr/include/c++/v1/ext
+	chmod 644 $(DSTROOT)/$(INSTALL_PREFIX)/usr/include/c++/v1/ext/*
 
 install:: installhdrs $(DESTDIR)
 
 	cd lib && ./buildit
 	ditto lib/libc++.1.dylib $(SYMROOT)/usr/lib/libc++.1.dylib
 	cd lib && dsymutil -o $(SYMROOT)/libc++.1.dylib.dSYM  $(SYMROOT)/usr/lib/libc++.1.dylib
-	mkdir -p $(DSTROOT)/usr/lib
-	strip -S -o $(DSTROOT)/usr/lib/libc++.1.dylib $(SYMROOT)/usr/lib/libc++.1.dylib
-	cd $(DSTROOT)/usr/lib && ln -s libc++.1.dylib libc++.dylib
+	mkdir -p $(DSTROOT)/$(INSTALL_PREFIX)/usr/lib
+	strip -S -o $(DSTROOT)/$(INSTALL_PREFIX)/usr/lib/libc++.1.dylib $(SYMROOT)/usr/lib/libc++.1.dylib
+	cd $(DSTROOT)/$(INSTALL_PREFIX)/usr/lib && ln -s libc++.1.dylib libc++.dylib