A bug in gmake?

[Story, Peter]

I *believe* this shows a bug in gmake in the maintenance of archives.

 

    GNU Make version 3.79.1, by Richard Stallman and Roland McGrath.
    Built for i386-redhat-linux-gnu
    Copyright (C) 1988, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 2000
     Free Software Foundation, Inc.
    This is free software; see the source for copying conditions.
    There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A
    PARTICULAR PURPOSE.

 

    Report bugs to <address@hidden>.

 

running on

 

    Linux SISPC1.ks-t.no 2.4.21-4.EL #1 Fri Oct 3 18:13:58 EDT 2003 i686 i686 i386 GNU/Linux

 

Run the showbug script, this is what I see:

 

    Here is the makefile, which uses the fast library maintenance strategy suggested
    in O'Reilly's Managing Projects with Make, 0-937175-90-0, 1991 edition,
    in the 'Nullifying Rules' section. This works fine on other makes I have used.
    --------------------
    libsicom.a:  libsicom.a(parser.o)
     $(CC) -c $(CFLAGS)    $(?:.o=.c)
     ar rv $@ $?; rm -f $?

 

    .c.a:;
    --------------------
    here are the files we use
    total 100
    -rw-rw-r--    1 petes    forsvar        34 Mar 11 09:23 stdmakefile
    -rw-rw-r--    1 petes    forsvar     42572 Mar 11 09:23 parser.c
    -rw-rw-r--    1 petes    forsvar        99 Mar 11 09:23 makefile
    -rw-rw-r--    1 petes    forsvar     38128 Mar 11 09:23 lex.lc
    -rw-rw-r--    1 petes    forsvar       637 Mar 11 09:35 ReadMe.txt
    -rwxrwxr-x    1 petes    forsvar       972 Mar 11 09:38 showbug
    --------------------
    create a library with something in it, not parser.o
    a - junk.o
    --------------------
    show the library contents ...
    rw-rw-r-- 5732/302  17648 Mar 11 09:39 2004 junk.o
    --------------------
    ask make what it has to do to make the library ...
    cc -c     parser.c
    ar rv libsicom.a parser.o; rm -f parser.o
    --------------
    ask it to do that and watch it fail to do so ...
    cc -c    
    cc: no input files
    make: *** [libsicom.a] Error 1
    --------------
    ask it to make the library with the slow inbuilt rules and watch it work ...
    cc    -c -o parser.o parser.c
    ar rv libsicom.a parser.o
    a - parser.o
    rm parser.o

 

I ask make how it would build the library and it tells me the correct answer.
Then I ask it to do it, and it can't.  What's going on?

 

Hope somebody feels inspired to find this one, we have lots of libraries
to move to gmake, and the many at a time technique is quite a lot more
effective

 

Cheers
Pete

Pete Story, Kongsberg Defence & Aerospace, Norway
mailto:address@hidden, +47 32286944

 

gmakebug.tar.gz
Description: gmakebug.tar.gz