Re: RFA: automatic dependency tracking

[Pedro Alves <pedro@codesourcery.com>]

On Wednesday 30 July 2008 20:05:01, Tom Tromey wrote:

> Pedro> I trust Tom.  :-)
>
> Thanks.  Though... we all make mistakes :)

I trust you to be around to fix them.

> One way you could help move this forward would be to test it on a
> machine that does not have GNU make.  I don't have one of these.

As you know, I tested building GDB with BSD make.  I used an x86
FreeBSD 6.0-RELEASE.

src/opcodes needs a little tweak to build,

  http://sourceware.org/ml/binutils/2008-07/msg00403.html

but other than that, pristine GDB builds fine with BSD make.

> The patch probably doesn't apply cleanly any more.  Unfortunately this
> sort of patch requires constant care to keep it up-to-date.

I tested with a checkout of the date of your patch to avoid that issue.

GDB built perfectly with your patch, with BSD make with and
without -j4 and with gmake also {,-j4}, always from a clean build dir.
I used:

 >gcc -v
 Using built-in specs.
 Configured with: FreeBSD/i386 system compiler
 Thread model: posix
 gcc version 3.4.4 [FreeBSD] 20050518

In addition to doing a couple of touch,make tests, to check if
dependencies are being respected with gmake, I tested building gdb
in a clean build dir, waiting a couple of minutes, and then
touching defs.h, and issuing gmake again.

By checking timestamps, I found that these are the files weren't
rebuilt by touching defs.h:

 18:19	..
 18:22	.gdbinit
 18:22	Makefile
 18:22	ada-exp.c
 18:22	ada-lex.c
 18:22	c-exp.c
 18:22	config.cache
 18:22	config.h
 18:22	config.log
 18:22	config.status
 18:22	cp-name-parser.c
 18:22	doc
 18:22	f-exp.c
 18:22	gnulib
 18:22	jv-exp.c
 18:22	m2-exp.c
 18:22	nm.h
 18:22	objc-exp.c
 18:22	observer.h
 18:22	observer.inc
 18:22	p-exp.c
 18:22	stamp-h
 18:22	stamp-h1
 18:22	stamp-xml
 18:22	testsuite
 18:22	version.c
 18:22	xml-builtin.c
 18:23	cp-name-parser.o
 18:23	version.o
 18:24	xml-builtin.o

With BSD make, touching header files doesn't trigger recompiles, as
expected.

-- 
Pedro Alves