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Re: make bin got dumb because of "Fix description in lily/include/smobs.
Re: make bin got dumb because of "Fix description in lily/include/smobs.hh"
Wed, 4 Jul 2012 00:39:00 +0200
On Tue, Jul 3, 2012 at 10:19 PM, David Kastrup <address@hidden> wrote:
> It is almost certainly a problem with your system clock. If you have
> touched source files with a future clock, and now the clock is right,
> then compiled files will be outdated ("older" than the source file)
> immediately after compilation again.
It sound very plausible, except for the fact that i've experienced
this behaviour after 'touch'ing all files in repository and doing make
from scratch... Well. nevermind. Fortunately it works now; if i get
this again i'll troubleshoot with precision.
On Tue, Jul 3, 2012 at 11:57 PM, Werner LEMBERG <address@hidden> wrote:
> There is a special built-in target in GNU make:
> If you specify prerequisites for `.LOW_RESOLUTION_TIME', `make'
> assumes that these files are created by commands that generate
> low resolution time stamps. The recipe for the
> `.LOW_RESOLUTION_TIME' target are ignored.
> The high resolution file time stamps of many modern file systems
> lessen the chance of `make' incorrectly concluding that a file is
> up to date. Unfortunately, some hosts do not provide a way to
> set a high resolution file time stamp, so commands like `cp -p'
> that explicitly set a file's time stamp must discard its
> subsecond part. If a file is created by such a command, you
> should list it as a prerequisite of `.LOW_RESOLUTION_TIME' so
> that `make' does not mistakenly conclude that the file is out of
> date. For example:
> .LOW_RESOLUTION_TIME: dst
> dst: src
> cp -p src dst
> Since `cp -p' discards the subsecond part of `src''s time stamp,
> `dst' is typically slightly older than `src' even when it is up
> to date. The `.LOW_RESOLUTION_TIME' line causes `make' to
> consider `dst' to be up to date if its time stamp is at the start
> of the same second that `src''s time stamp is in.
> Maybe this helps?
I don't think i'm going to mess with this issue again, but
nevertheless thanks for this information - it may come in handy one