[build2] Trigger compile of sources when their header dependencies change

[Moldmann Max (DC-MA/ENG52-NA)]

Hi Boris,

file-a.o.d contains:

1
c.compile 1
hash1
hash2
file-a.c

but does not contain "file-a.h". 
But the file-a.d contains the header file:

module-a\_src\file-a.o: module-a\_src\file-a.c \
  module-a\_src\/../_inc/file-a.h

This is on Windows 10.

File        | Touch     | Modify
file-a.h   |      x        |     -        no compile of file-a.c (good as hash has not changed)
file-a.c   |      x        |     -        no compile of file-a.c (good as hash has not changed)
file-a.h   |      -        |     x        no compile of file-a.c (<-- This is the bad case)
file-a.c   |      -        |     x        compile of file-a.c (good)


When I manually add the header file to the end of the o.d file then everything works as expected!

Max

-----Original Message-----
From: Boris Kolpackov [mailto:boris at codesynthesis.com] 
Sent: Tuesday, April 11, 2017 9:26 AM
To: Moldmann Max (DC-MA/ENG52-NA) <Max.Moldmann at boschrexroth-us.com>
Cc: users at build2.org
Subject: Re: [build2] Trigger compile of sources when their header dependencies change

Hi Max,

Moldmann Max (DC-MA/ENG52-NA) <Max.Moldmann at boschrexroth-us.com> writes:

> I noticed that build2 doesn't compile file-a.c when an included header 
> file i.e. file-a.h is changed.

That's strange, this feature has been implemented and working for us for a long time now. You can check for this header in the "aux dependency database" file (file-a.o.d).

If this indeed does not work, I will need a simple project that reproduces this problem as well as the description of the environment (if this is Windows, perhaps it has something to do with timestamp resolution...).

Boris