From: "Andrew Crabtree" Newsgroups: comp.os.msdos.djgpp Subject: Re: How is the MAKE work currentlly... Date: Wed, 27 May 1998 13:41:11 -0700 Organization: Hewlett-Packard, Roseville Lines: 10 Message-ID: <6khtot$ohp$1@rosenews.rose.hp.com> References: <356c3a56 DOT 2602522 AT news DOT ficnet DOT net DOT tw> NNTP-Posting-Host: ros51675cra.rose.hp.com To: djgpp AT delorie DOT com DJ-Gateway: from newsgroup comp.os.msdos.djgpp Precedence: bulk otto wrote in message <356c3a56 DOT 2602522 AT news DOT ficnet DOT net DOT tw>... >> When I modified the header file, > the make can't find the global file is modified. Usually your make rules for foo.o say to only rebuild if foo.c has changed. Not foo.h. You either need to manually add the header file to your list of dependencies, or use something like make depends.