From b4b36a27489dc4086b6aa04957adaa46b2740675 Mon Sep 17 00:00:00 2001
From: Jacob Dahl <37091262+dakejahl@users.noreply.github.com>
Date: Sun, 17 May 2026 18:00:06 -0400
Subject: [PATCH] fix(nuttx): unblock multi-board and protected builds (#27360)

* fix(ci): wipe NuttX submodule state between boards in build_all_runner

NuttX .o and lib*.a live in the shared submodule trees under
platforms/nuttx/NuttX/{nuttx,apps}, not in per-board build/<board>/.
NuttX's recursive make doesn't treat PX4's per-board defconfig changes
as a reason to recompile, so consecutive board builds in one workspace
were linking stale objects from an earlier board (e.g. stm32_spi.o from
fmu-v2 linked into fmu-v4pro, which doesn't enable SPI4).

Run git clean -dXf on both NuttX submodules between iterations to drop
gitignored build state. This mirrors what make clean already does for
submodules and preserves the incremental-build wins for single-board
use.

* fix(cmake): isolate kernel mm/libc objects with BINDIR=kbin

mm and libs/libc compile the same sources for both the kernel and user
passes in protected builds. Without separate output dirs the kernel
objects clobber bin/*.o and the user-mode libmm.a/libc.a end up pulling
in kernel-only symbols (nxsem_wait, g_current_regs, nx_read, nx_write,
g_mmheap, ...) at link time. Matches NuttX's own tools/LibTargets.mk.
---
 Tools/ci/build_all_runner.sh         | 9 +++++++++
 platforms/nuttx/NuttX/CMakeLists.txt | 9 ++++++++-
 2 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/Tools/ci/build_all_runner.sh b/Tools/ci/build_all_runner.sh
index a47d42dd87..132b634ebd 100755
--- a/Tools/ci/build_all_runner.sh
+++ b/Tools/ci/build_all_runner.sh
@@ -3,6 +3,14 @@
 # Please only modify if you know what you are doing
 set -e
 
+# NuttX .o/.a live in the shared submodule trees, not per-board build dirs.
+# Wipe them between boards so stale objects from a prior board's defconfig
+# don't get linked into the next board's elf.
+clean_nuttx_state() {
+    git -C platforms/nuttx/NuttX/nuttx clean -dXf -q
+    git -C platforms/nuttx/NuttX/apps  clean -dXf -q
+}
+
 targets=$1
 for target in ${targets//,/ }
 do
@@ -14,4 +22,5 @@ do
     build_time="$(($diff /60/60))h $(($diff /60))m $(($diff % 60))s elapsed"
     echo -e "\033[0;32mBuild Time: [$build_time]"
     echo "::endgroup::"
+    clean_nuttx_state
 done
diff --git a/platforms/nuttx/NuttX/CMakeLists.txt b/platforms/nuttx/NuttX/CMakeLists.txt
index 3a700ce9ff..30182a722c 100644
--- a/platforms/nuttx/NuttX/CMakeLists.txt
+++ b/platforms/nuttx/NuttX/CMakeLists.txt
@@ -181,8 +181,15 @@ function(add_nuttx_dir nuttx_lib nuttx_lib_dir kernel extra target)
 		${CMAKE_CURRENT_SOURCE_DIR}/nuttx/${nuttx_lib_dir}/*.h
 	)
 
+	# Route kernel pass for mm/libc to kbin/; user pass uses bin/ for the
+	# same sources and would otherwise overwrite the kernel objects.
+	set(bindir_arg)
+	if(${kernel} STREQUAL y AND (${nuttx_lib_dir} STREQUAL mm OR ${nuttx_lib_dir} STREQUAL libs/libc))
+		set(bindir_arg BINDIR=kbin)
+	endif()
+
 	add_custom_command(OUTPUT ${CMAKE_CURRENT_BINARY_DIR}/nuttx/${nuttx_lib_dir}/lib${nuttx_lib}.a
-		COMMAND make -C ${nuttx_lib_dir} --no-print-directory --silent ${nuttx_lib_target} TOPDIR="${NUTTX_DIR}" KERNEL=${kernel} EXTRAFLAGS=${extra}
+		COMMAND make -C ${nuttx_lib_dir} --no-print-directory --silent ${nuttx_lib_target} TOPDIR="${NUTTX_DIR}" KERNEL=${kernel} EXTRAFLAGS=${extra} ${bindir_arg}
 		COMMAND ${CMAKE_COMMAND} -E copy_if_different ${NUTTX_DIR}/${nuttx_lib_dir}/lib${nuttx_lib}.a ${CMAKE_CURRENT_BINARY_DIR}/nuttx/${nuttx_lib_dir}/lib${nuttx_lib}.a
 		DEPENDS
 			${nuttx_lib_files}