[bug #59169] Add a --debug=why category for the -d/--debug option

[David Boyce]

Follow-up Comment #3, bug #59169 (project make):

I've updated the patch a bit to coalesce message style. The current --trace
output comes in one of two formats:

Makefile:12: target 'foobar' does not exist
Makefile:15: update target 'hello.o' due to: hello.c

According to whether there's a valid $?. This is unsatisfying for a few
reasons:

1. Having two different formats for the same type of output with no common
keyword makes trace output inherently harder to find reliably either visually
or via grep et al.

2. In fact it's not at all clear to the newbie, without inspecting GNU make
source code, that the "foobar does not exist" message is part of --trace
output at all since "file does not exist" is one of the more common error
conditions across the SW industry and could be printed by any number of
unrelated recipes.

3. The message isn't anchored in time: does the target not exist _before_ or
_after_ the recipe runs? When read literally it's incorrect since the target
definitely does exist by the time the user sees the message.

I think it works better when the message is either:

Makefile:12: update target 'foobar' due to: does not exist
Makefile:15: update target 'hello.o' due to: hello.c

It might read even better if "does not exist" became "nonexistent" but I
decided to defer that to Paul.

(file #49877)
    _______________________________________________________

Additional Item Attachment:

File name: debug_print_why2.patch         Size:3 KB
    <https://file.savannah.gnu.org/file/debug_print_why2.patch?file_id=49877>



    _______________________________________________________

Reply to this item at:

  <https://savannah.gnu.org/bugs/?59169>

_______________________________________________
  Message sent via Savannah
  https://savannah.gnu.org/