[RTEMS Project] #3481: Update no_cpu/no_bsp for currently applicable advice

[RTEMS trac]

#3481: Update no_cpu/no_bsp for currently applicable advice
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  Reporter:  Amaan Cheval  |      Owner:  (none)
      Type:  enhancement   |     Status:  new
  Priority:  normal        |  Milestone:
 Component:  doc           |    Version:
  Severity:  minor         |   Keywords:
Blocked By:                |   Blocking:
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 The no_bsp code is often outdated, including functions that are considered
 legacy and advice that may not apply or may be insufficient now.

 We should update it to reflect the current approach RTEMS takes in the
 general sense.

 Some observations:

 * no_bsp doesn't include irq-sources.am, which is critical for parts of
 the libbsd stack
 * no_bsp uses bsp_specs to add "-lrtemsbsp -lrtemscpu", without indication
 on how most other architectures carry that functionality out (i.e.
 [https://github.com/gcc-
 mirror/gcc/blob/8c422d602fd45b5cbfe08fa8e66c4150ec1f1373/gcc/config/rtems.h#L40-L44
 through GCC itself])
 * no_bsp's linkcmds has no indication of required sections (TLS,
 rtemsroset, rtemsstack), or where to start building the linker script from
 (target-ld --verbose)
 * no_bsp's no_bsp.cfg should also document other possible options (like
 CPU_CFLAGS)

 I'll add others as they come to me.

--
Ticket URL: <http://devel.rtems.org/ticket/3481>
RTEMS Project <http://www.rtems.org/>
RTEMS Project