On 2016-05-24 01:02, Kieran Bingham wrote: > Hi Kbuild / Michal, > > I've been working through a problem that Jan has reported whereby if we > modify a file included by our template for constants.py, the generated > file is not rebuilt. > > The rule/cmd [0] to generate the python constants is > cmd_gen_constants_py which uses the $(CPP) with $(c_flags) to create the > output. > > One benefit of this is that it already creates the $(depfile) through > the addition of the flags provided by $(c_flags), however as yet it > would seem that my efforts to understand how the $(depfile) gets > included have failed. > > From what I can tell, the $(call if_changed...) rule is generating my > targets .constants.py.cmd, but the .d file is not being utilised. > > By swapping $(call if_changed, ) to $(call if_changed_dep,...) I can see > that my .constants.py.cmd [1] file now has (apparently) correct > dependency rules being generated. However they still don't take actual > effect. If I 'touch/modify' one of the files I have added to the > #includes, then my target is not rebuilt (I have added > include/linux/kieran.h for testing this specifically without rebuilding > all other objects) Hi Kieran, sorry for the late reply. In case this is still relevant: For if_changed/if_changed_dep to work, you must list the target in the $(targets) list (without the $(obj) prefix) and add FORCE as a prerequisite of the rule. Michal -- To unsubscribe from this list: send the line "unsubscribe linux-kbuild" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
