[PATCH] kbuild: Eliminate build error when KALLSYMS not defined

The following build error happens with 2.6.14-rc4 when CONFIG_KALLSYMS is
not defined. The error message in a fragment of the output was:

CC arch/i386/lib/usercopy.o
AR arch/i386/lib/lib.a
/bin/sh: line 1: +@: command not found
make[3]: warning: jobserver unavailable: using -j1. Add `+' to parent make rule.
CHK include/linux/compile.h

Signed-off-by: Mark Rustad <[e-mail]>
Signed-off-by: Sam Ravnborg <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

Makefile

···
 # Link of vmlinux
 # If CONFIG_KALLSYMS is set .version is already updated
 # Generate System.map and verify that the content is consistent
-
+# Use + in front of the vmlinux_version rule to silent warning with make -j2
+# First command is ':' to allow us to use + in front of the rule
 define rule_vmlinux__
+	:
 	$(if $(CONFIG_KALLSYMS),,+$(call cmd,vmlinux_version))
 
 	$(call cmd,vmlinux__)