[RFC PATCH 0/1] Change newlib configuration to require libgloss

[RFC PATCH 0/1] Change newlib configuration to require libgloss

[Mark Hatle]

This is an RFC, because I only know of my particular use-case.  So I'm not
sure how generic of a change this really is.

In my own use-case, we want to build a generic newlib and then customize
our equivalent to libgloss when linking baremetal applications.

I found that if we don't pass --disable-newlib-supplied-syscalls, even if
libgloss was linked in, the syscalls -always- came from newlib (on 32-bit
arm) and would not permit my implementations to override the built-in
newlib versions.

By setting the disable in BOTH newlib an libgloss, newlib syscalls are
disabled, while libgloss syscalls are enabled.  This results in a newlib
that will now require to be linked against a 'BSP' implementation, such
as libgloss, in order to build baremetal applications.

Alternatively to this I'd suggest we add pkgconfigs (or even distro
flags) to be able to change this behavior as well as flip some other
newlib switches if desired.

Mark Hatle (1):
  newlib: Move syscalls from newlib to libgloss

 meta/recipes-core/newlib/newlib.inc | 1 +
 1 file changed, 1 insertion(+)

-- 
2.17.1

[RFC PATCH 1/1] newlib: Move syscalls from newlib to libgloss

[Mark Hatle]

By passing --disabled-newlib-supplied-syscalls, newlib will disable the
generation of builtin syscalls and move this to libgloss.  (This also
affects the generation of crt0.o.)

libgloss SHOULD then provide the syscalls, crt0.o and other functions that
are no longer part of newlib itself.  This now means that you must link
with both newlib and libgloss, whereas before newlib would run in many
configurations by itself.

Signed-off-by: Mark Hatle <mark.hatle@kernel.crashing.org>
---
 meta/recipes-core/newlib/newlib.inc | 1 +
 1 file changed, 1 insertion(+)

diff --git a/meta/recipes-core/newlib/newlib.inc b/meta/recipes-core/newlib/newlib.inc
index d7ac8bff17..5edea8aba1 100644
--- a/meta/recipes-core/newlib/newlib.inc
+++ b/meta/recipes-core/newlib/newlib.inc
@@ -42,6 +42,7 @@ EXTRA_OECONF = " \
 		--with-gnu-as \
 		--with-gnu-ld \
 		--disable-multilib \
+		--disable-newlib-supplied-syscalls \
 		"
 
 do_configure[cleandirs] = "${B}"
-- 
2.17.1