Preventing compilation of a C file

I have run into some interesting behaviour I think. I have a rule like
this:

 opcodes.h : vdbe.c
         :print /* Automatically generated file.  Do not edit */ >!  $(target)
	 :sys grep '^case OP_' vdbe.c | \
	   sed -e 's/://' | \
           awk '{printf "#define %-30s %3d\n", $$2, ++cnt}' >> $(target)

The result of running aap on this is:

 Aap: Creating directory "/home/magnus/prog/tmp/sqlite/src/build-Linux2_6_7_1_k7"
 Aap:  cc       -MM vdbe.c > build-Linux2_6_7_1_k7/vdbe.c.aap
 In file included from vdbe.c:48:
 sqliteInt.h:19:20: config.h: No such file or directory
 sqliteInt.h:20:21: sqlite3.h: No such file or directory
 sqliteInt.h:22:19: parse.h: No such file or directory
 Aap: Error in recipe "/usr/lib/aap/default.aap" line 161: :update failed for "config.h"

Why does aap insist on compiling vdbe.c?
How do I prevent it from doing so?

/M

-- 
Magnus Therning                    (OpenPGP: 0xAB4DFBA4)
[email protected]
http://magnus.therning.org/

It's a damn poor mind that can only think of one way to spell a word.
     -- Andrew Jackson

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