Fake demo_xe.mk found in Oracle eXpress Edition,
known by CPAN DBD::Oracle (bug#165834).
This provides absolute paths for headers and libraries.
--- instantclient_18_3/sdk/demo/demo.mk
+++ instantclient_18_3/sdk/demo/demo.mk
@@ -28,13 +28,18 @@
 CC=/opt/SunProd/SUNWspro6.1/bin/CC
 cc=/opt/SunProd/SUNWspro6.1/bin/cc
 
-ICINCHOME=../
-ICLIBHOME=../../
+ifeq ($(BUILD32),T)
+LIBDIR=lib32
+else
+LIBDIR=lib
+endif
+ICINCHOME=$(ORACLE_HOME)/include
+ICLIBHOME=$(ORACLE_HOME)/$(LIBDIR)
 ICLIBPATH=-L$(ICLIBHOME)
 THREADLIBS=-lthread
 CCLIB=$(ICLIBPATH) -locci -lclntsh $(THREADLIBS)
 
-CCINCLUDES = -I$(ICINCHOME)include
+CCINCLUDES = -I$(ICINCHOME)
 
 CCFLAGS=$(CCINCLUDES) -D_REENTRANT -g -xs 
 LDFLAGS=
@@ -55,10 +60,10 @@
 OCCIOTTPWD=tiger
 
 .cpp.o:
-	$(CC) -c -I$(ICINCHOME)include $(CCFLAGS) $<
+	$(CC) -c -I$(ICINCHOME) $(CCFLAGS) $<
 
 .c.o:
-	$(cc) -c -I$(ICINCHOME)include $(CCFLAGS) $<
+	$(cc) -c -I$(ICINCHOME) $(CCFLAGS) $<
 
 all: clean buildoci $(OCCIDEMO) $(OCCIOBJDEMO)