Re: Generating missing depfiles by an automake based makefile

[Jan Engelhardt]

On Thursday 2023-02-09 22:33, Dmitry Goncharov wrote:
>
>> .Po file contents control when an .o file -- and thus also
>> the .Po file itself -- is remade.
>> If a .Po file has no practical content, there is no indication
>> that it needs to be remade.
>
>Absence of the depfile is such an indication.
>Here is a sample bash session which demonstrates how gnu make and sun
>make are able to build a missing depfile.
>
>$ ls
>hello.c  hello.h  makefile
>$ cat makefile
>all: hello.tsk
>hello.tsk: hello.o
>        gcc-10 -o $@ $^
>
>hello.o: hello.c hello.Po
>        gcc-10 -c hello.c -MD -MF hello.Po
>
>hello.Po:
>        gcc-10 -c hello.c -MD -MF hello.Po
>
>include hello.Po

This is a GNU extension. If you try this with e.g.
OpenBSD make, it will complain.