Re: 32 bits time_t and Y2038 issue

On 21/03/2025 21:53, Michael Schwingen wrote:

On 2025-03-21, David Brown <david.brown@hesbynett.no> wrote:

>
The way I use recursive makes is /really/ recursive - the main make
(typically split into a few include makefiles for convenience, but only
one real make) handles everything, and it does some of that be calling
/itself/ recursively.  It is quite common for me to build multiple
program images from one set of source - perhaps for different variants
of a board, with different features enabled, and so on.  So I might use
"make prog=board_a" to build the image for board a, and "make
prog=board_b" for board b.  Each build will be done in its own directory
- builds/build_a or builds/build_b.  Often I will want to build for both
boards - then I will do "make prog="board_a board_b"" (with a default
setting for the most common images).

 OK, that is not the classic recursive make pattern (ie.  run make in each
subdirectory).

Agreed - it is not the pattern that the famous paper warned against. But it /is/ recursive make.  And in general, I think recursive make can potentially be useful in various ways, but you have to be very careful about how you use it in order to do so safely (and efficiently - but of course safety and correctness is the priority).

 I do that (ie.  building for multiple boards) using build
scripts that are external to make.
 cu
Michael