ifeq in gmake

[atteson]

Can someone explain why gmake outputs "goodbye" rather than "hello"
with the following test makefile:

%.a : b
ifeq ($@,"a.a")
    echo "hello"
else
    echo "goodbye"
endif

I named the makefile "test" and I run it with "make -f test a.a".  I
created a file called "b" but there is no file called "a.a".