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To: Masahiro Yamada <yamada.masahiro@socionext.com>
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From: Cao jin <caoj.fnst@cn.fujitsu.com>
Subject: special handle of scripts/kconfig/zconf.tab.o
Message-ID: <5992D4DF.2080405@cn.fujitsu.com>
Date: Tue, 15 Aug 2017 19:02:55 +0800
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Masahiro-san,

I have a question about make *config. In scripts/kconfig/Makefile, there
is following statement:

$(obj)/zconf.tab.o: $(obj)/zconf.lex.c $(obj)/zconf.hash.c

and the $(obj)/zconf.{tab,hash,lex}.c match the rule in Makefile.lib:

$(obj)/%: $(src)/%_shipped
        $(call cmd,shipped)

and cmd_shipped just transform the _shipped file to .c via `cat`.

And zconf.tab.c includes several *other* .c files which make the whole
process a little obscure, because there are not corresponding .o files
for the *other* .c files.

My questions is: Does this special handling has other meanings that I
may miss? Or just legacy.

Because a straightforward way in my mind would be:

rename zconf.{tab,hash,lex}.c_shipped to zconf.{tab,hash,lex}.c, then
has following in the Makefile

common-objs := zconf.tab.o zconf.hash.o zconf.lex.o util.o etc...
conf-objs := conf.o $(common-objs)

-- 
Sincerely,
Cao jin