behavior on Win depends on whether \ or / is used??

[Mark Galeck (CW)]

Hello,  this is a Windows question, 

I have 2 subdirectories foobar0 and foobar1, and only in foobar1 there is a 
file foobar.s  . There is no file foobar.o .  

The makefile is:


SHELL=cmd.exe
                
vpath %.s .\foobar0 .\foobar1   

%.o : %.s 
                echo $<

foobar0\foobar.s:;


This behaves as expected:

C:\tmp>make foobar.o
echo .\foobar1/foobar.s


However, if I change all the backslashes to forward-slashes, then I get:


C:\tmp>make foobar.o
make: *** No rule to make target `foobar.s', needed by `foobar.o'.  Stop.

(this is just a small example, what I observe is that forward slash in 
directories, misbehaves with vpath on Windows)

Is this a bug in Windows make, or in my head?  

Mark