0005234: Selecting MTD utils from git doesn't give you the HEAD

Notes
(0012684) mjd 10-03-08 09:42	diff -x config -u -r buildroot-mtcba-g1-pristine/package/mtd/mtd-utils.git/mtd.mk buildroot-mtcba-g1/package/mtd/mtd-utils.git/mtd.mk --- buildroot-mtcba-g1-pristine/package/mtd/mtd-utils.git/mtd.mk 2008-08-03 14:11:27.000000000 +1000 +++ buildroot-mtcba-g1/package/mtd/mtd-utils.git/mtd.mk 2008-09-30 17:45:07.000000000 +1000 @@ -3,7 +3,7 @@ # mtd provides jffs2 utilities # ############################################################# -MTD_VERSION:=fcb52ccc99679460640386c297023f852b108f68 +MTD_VERSION:=HEAD MTD_SOURCE:=mtd-utils-$(MTD_VERSION).tar.gz MTD_URL:=http://git.infradead.org/mtd-utils.git?a=snapshot;h=$(MTD_VERSION);sf=tgz [^] MTD_HOST_DIR:= $(TOOL_BUILD_DIR)/mtd-utils-$(MTD_VERSION)

(0012694) bernhardf 10-03-08 10:01	may i suggest you add a config BR2_PACKAGE_MTD_UTILS_GIT_REVISION string "git revision" default "HEAD" if !BR2_avr default "the_previous_hash" if BR2_avr32 help Here you can enter the git revision you want to use. Usually this will be "HEAD", but if you could add some other hash here. Just a thought..

(0012714) mjd 10-03-08 16:47	Hi bernhardf, I like that idea. However my config.in-fu is not yet good enough to do what you suggested. If you want to do it, could you (or someone else) write it and try it out please?

(0012724) mjd 10-03-08 16:49	Guys, there may be a problem with using mtd-util from HEAD. Please give me a little time to work out what's happening with that code.

(0012904) egtvedt 10-06-08 22:00	There is also no need to special handle AVR32. AVR32 works fine with the latest release of MTD.

(0012914) mjd 10-07-08 00:07	I'm not sure why yet, but at the moment, I can build "mtd-host", but I can't build "mtd". mtd-utils-HEAD has a file called "fec.c". This file is trying to use bcopy and bzero. It also has macros to work out whether it has to fake the existence of bcopy and bzero. The compile warnings and link errors I get are that there's a mismatch between the definitions of those internals, and what's in fec.c. Does anyone else have this problem? Does fec.c compile for your target?

(0012984) hmoffatt 10-07-08 06:17	I think that using HEAD by default is not a good idea. I did this originally. Problem is that it'll download head once, but nothing will cause it to download head again (unless you remove the .tar.gz from the sources directory). AND you don't know what version you have either if you want to rebuild later. Also, the patches won't necessarily apply to a later version. A configuration option would be an improvement though it doesn't solve the patch problem. I think it really needs manual intervention, which is how it came to be how it is now.

(0012994) hmoffatt 10-07-08 06:20	Re: HEAD not compiling in fec.c, this is why the package shouldn't just track HEAD :) Better to patch fec.c to use memcopy/memset instead of bcopy/bzero I think; the latter are only enabled if configured that way in uclibc, and even then I've had problems in the past. So by all means submit a patch which makes a recent revision compile but please don't use the HEAD symbolic name. Even better if you can use a tagged released version rather than a commit id.

(0013004) mjd 10-07-08 06:36 edited on: 10-07-08 06:38	All good points, but if the menu says "git", but it gives you a certain non-HEAD snapshot, it violates the "principle of least surprise". And I was certainly surprised to find out the "git" version was several months old. (How did I find out it wasn't HEAD? I wanted features in the latest upstream version that were missing in the buildroot one, and wasted several days making mods to the out-of-date one that I then had to port to the latest version) If I select "mtd-utils from git", it pretty much sets the expectation of a moving target. If you can't afford the moving target, don't choose the git version! :-) As a way forward, if we don't make the "git" choice use the HEAD, can we update the menus to say the date of the version we've endorsed, instead of saying "git"? (That's what the "git" option at the moment effectively does)? After all, when "git" is selected, it doesn't even use git! :-) For better or worse, we already have the mechanisms to support different patches for different versions of MTD. If I provide a version that DOES update itself when upstream mtd-utils changes, is that ok?

(0013014) hmoffatt 10-07-08 06:46 edited on: 10-07-08 06:46	Fair points. I think I had it track HEAD initially but ran into those two problems I mentioned, specifically that 1. it wouldn't download updated versions, and 2. it's difficult to manage patches. Item 1 could be solved by using git to check out the source (and then you'd probably have to do it every time you ran make, which would be slow), rather than HTTP. I didn't feel like writing a package for GIT itself just to solve this. If there's some way to get a daily snapshot via HTTP that might be an improvement. Item 2 is harder. Any given patch might be needed for a range of versions only. Later versions may not compile without patches. I think item 2 means that you really have to add new versions by hand, but I'm happy to be proven wrong. I'm happy for us to change the naming/Config.in etc to advertise that this is not the latest from GIT but a particular GIT snapshot. Patch gratefully accepted or else I'll look at it myself later in the week.

(0013024) mjd 10-07-08 17:10	HEAD should be a synonym for some version accessible via those long digest hex string thingys, for example, I'm sure the present value of fcb52ccc99679460640386c297023f852b108f68 was once accessible via HEAD. If we had some way of looking up (via HTTP interface) what the current HEAD was (in terms of its equivalent digest value) we could compare that to the version stamp of when we first retrieved the source. If it differed, we could retrieve the difference and apply it as a patch, updating that local version stamp. Yeah I know, a bit grotty. Is it possible to have both? That is, we rename what is currently "git" to become just another dated snapshot, and "git" becomes HEAD?

(0013034) mjd 10-07-08 17:54	Reported fec.c/bcopy problem to upstream: http://lists.infradead.org/pipermail/linux-mtd/2008-October/023173.html [^]

Issue History
Date Modified	Username	Field	Change
10-03-08 09:40	mjd	New Issue
10-03-08 09:40	mjd	Status	new => assigned
10-03-08 09:40	mjd	Assigned To	=> buildroot
10-03-08 09:40	mjd	File Added: mtd-utils-git-from-head-1.diff
10-03-08 09:42	mjd	Note Added: 0012684
10-03-08 10:01	bernhardf	Note Added: 0012694
10-03-08 16:47	mjd	Note Added: 0012714
10-03-08 16:49	mjd	Note Added: 0012724
10-06-08 22:00	egtvedt	Note Added: 0012904
10-07-08 00:07	mjd	Note Added: 0012914
10-07-08 06:17	hmoffatt	Note Added: 0012984
10-07-08 06:20	hmoffatt	Note Added: 0012994
10-07-08 06:36	mjd	Note Added: 0013004
10-07-08 06:38	mjd	Note Edited: 0013004
10-07-08 06:46	hmoffatt	Note Added: 0013014
10-07-08 06:46	hmoffatt	Note Edited: 0013014
10-07-08 17:10	mjd	Note Added: 0013024
10-07-08 17:54	mjd	Note Added: 0013034

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