.\"
.\"	aegis - project change supervisor
.\"	Copyright (C) 1998 Peter Miller;
.\"	All rights reserved.
.\"
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.\"	the Free Software Foundation; either version 2 of the License, or
.\"	(at your option) any later version.
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.\"	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
.\"	GNU General Public License for more details.
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.\"	along with this program; if not, write to the Free Software
.\"	Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111, USA.
.\"
.\" MANIFEST: AUUGN Feb'98 Article
.\"
.nr PS 72
.nr VS 75000
.LP
.ad c
How Make Works
.br
.ad l
.sp 0.3i
.nr PS 36
.nr VS 37
.XP
\(bu
The Makefile is turned into pair-wise ordered dependencies.
.br
.ps 16
.vs 17
.sp 0.5
.TS
tab(;);
lf(CW) l.
prog: a.o b.o;prog \(<- a.o
    cc a.o b.o -o prog;prog \(<- b.o
.sp 0.5
a.o: a.c a.h;a.o \(<- a.c
    cc -c a.c;a.o \(<- a.h
.sp 0.5
b.o: b.c a.h;b.o \(<- b.c
    cc -c b.c;b.o \(<- a.h
.sp 0.5
a.c a.h: a.y;a.c \(<- a.y
    yacc -d a.y;a.h \(<- a.y
    \fImv \&...\fI
.TE
.XP
\(bu
The pairs are then shuffled to find a valid ordering.
.bp
.nr PS 24
.nr VS 25
.XP
\(bu
The Makefile is turned into pair-wise ordered dependencies.
.XP
\(bu
The order of appearance of the rules in the Makefile doesn't mean anything.
.XP
\(bu
There is more than one valid ordering.
.XP
\(bu
Recall \fIlorder\fP and \fItsort\fP from the days before \fIranlib\fP?
Same thing.
.br
\(dg Only nastier, because of pattern rules.