nuttx/arch
Marco Casaroli 72f088ea8f arch/arm: Reserve r10 via ARCHCFLAGS and hoist the PIC module flags.
Toolchain.defs adds --fixed-r10 to CFLAGS under CONFIG_PIC, but nearly
every board Make.defs includes that file and then assigns

  CFLAGS := $(ARCHCFLAGS) $(ARCHOPTIMIZATION) $(ARCHCPUFLAGS) ...

with ':=', which discards it.  266 of the 269 ARM board files assign
CFLAGS that way; the remaining three delegate to a shared makefile that
does the same thing.

The flag is what keeps the base firmware from allocating r10, the
register a PIC module reaches its own data through.  Losing it is silent
and the symptom is remote from the cause: the build succeeds, and only a
callback from base firmware into module code -- qsort() with a module
comparison function is the standard case -- misbehaves, reading its data
through a register the firmware has since felt free to reuse.

Adding it to ARCHCFLAGS puts it on the far side of that ':=', which
re-expands ARCHCFLAGS, so every board picks it up with no board changes
at all.

A module is the other side of the --fixed-r10 contract: it gets r10 via
-mpic-register=r10, and GCC rejects both on one command line with
"unable to use 'r10' for PIC register".  Every ARM board carried the
same three lines to set that up:

  ARCHPICFLAGS = -fpic -msingle-pic-base -mpic-register=r10
  CPICFLAGS = $(ARCHPICFLAGS) $(CFLAGS)
  CXXPICFLAGS = $(ARCHPICFLAGS) $(CXXFLAGS)

They move to arch/arm/src/common/Toolchain.defs, which also filters
--fixed-r10 back out of CPICFLAGS, CXXPICFLAGS, CELFFLAGS and
CXXELFFLAGS in one place instead of each board having to know about the
interaction.  ARCHPICFLAGS uses '?=' and the derived flags use deferred
'=', so a board can still override or append after including the file,
and CFLAGS is whatever the board finally set it to.

Two boards keep a definition because they genuinely differ: am67 adds
-ffixed-r10 and tiva conditionally adds -mno-pic-data-is-text-relative.
tlsr82 previously appended -fpic to an unset variable, so only -fpic
ever reached its compiler; it now inherits the standard set, verified
against tc32-elf-gcc 4.5.1.tc32-elf-1.5 (Telink TC32 v2.0), whose
ARM-derived backend honors -msingle-pic-base and -mpic-register=r10.
The mps2, mps3, qemu-armv7a, qemu-armv7r, fvp and mcx-nxxx families
referenced ARCHPICFLAGS without ever defining it, so their CPICFLAGS
carried no PIC flags at all; they get the standard set too.

Also adds the missing space in

  CXXELFFLAGS = $(CXXFLAGS)-fvisibility=hidden -mlong-calls

which ran the last token of CXXFLAGS into -fvisibility=hidden, yielding
a single malformed token such as -DNDEBUG-fvisibility=hidden.

Also exempts the pre-existing "*.siz" gsize comment in Toolchain.defs
from codespell, which reads "siz" as a misspelling and fires for any
patch touching the file, since checkpatch scans whole files rather than
changed lines.

Before, with CONFIG_PIC=y:  CFLAGS has --fixed-r10: NO
After:                      CFLAGS has --fixed-r10: YES
                            CPICFLAGS/CELFFLAGS:    filtered out

Assisted-by: Claude Code:claude-opus-4-8
Assisted-by: Claude Code:claude-fable-5
Signed-off-by: Marco Casaroli <marco.casaroli@gmail.com>
2026-07-24 13:17:12 +02:00
..
arm arch/arm: Reserve r10 via ARCHCFLAGS and hoist the PIC module flags. 2026-07-24 13:17:12 +02:00
arm64 arm64: add RK3588 support 2026-07-20 20:55:52 -03:00
avr arch/avr/src/avrdx/avrdx_delay: add custom up_udelay function 2026-06-12 09:55:11 -04:00
ceva arch/ceva: Replace board_app_initialize 2026-05-02 18:36:46 +08:00
dummy
hc style: fix checkpatch issues after debug.h move 2026-04-07 07:50:06 -03:00
mips arch/mips/jz4780: Add support for L2 cache operations 2026-07-21 16:40:08 +08:00
misoc include/debug.h: Move to include/nuttx/debug.h 2026-04-07 07:50:06 -03:00
or1k include/debug.h: Move to include/nuttx/debug.h 2026-04-07 07:50:06 -03:00
renesas drivers/efuse/efuse: Drivers Registered With World Write Permissions(Part 1) 2026-07-13 12:08:01 +02:00
risc-v arch/risc-v/espressif: Fix build errors on CMake ULP build system 2026-07-20 08:20:26 -03:00
sim !include/fcntl.h: align open flags with Linux values 2026-06-30 13:43:44 +08:00
sparc drivers: Fix comment typos — 'Pubic' → 'Public' across drivers and headers. 2026-07-02 13:29:48 +08:00
tricore arch/tricore: Add hardware debug breakpoint and watchpoint support. 2026-05-22 15:38:36 +08:00
x86 drivers/efuse/efuse: Drivers Registered With World Write Permissions(Part 1) 2026-07-13 12:08:01 +02:00
x86_64 !include/fcntl.h: align open flags with Linux values 2026-06-30 13:43:44 +08:00
xtensa drivers/: Multiple Drivers Are Registered With World Writable - Part 2 2026-07-15 15:27:28 +08:00
z16 include/debug.h: Move to include/nuttx/debug.h 2026-04-07 07:50:06 -03:00
z80 style: fix checkpatch issues after debug.h move 2026-04-07 07:50:06 -03:00
CMakeLists.txt
Kconfig sched/clock/clock_delay: added config flag to remove weak up_udelay 2026-06-12 09:55:11 -04:00