aff8ea572a
boards/sim/sim/sim/scripts/Make.defs adds `-no-pie` to ARCHCFLAGS /
ARCHPICFLAGS / LDFLAGS for every 64-bit non-Mac sim build. The
original comment ("To compile 64-bit Sim, adding no-pie is necessary
to prevent linking errors but this may cause other issues on
Ubuntu 20.") already flagged the workaround as fragile.
On HOST_ARM64 the option is in fact actively harmful. When gcc is
asked to produce a non-PIE executable on aarch64 it switches the
libgcc resolution path from the dynamic library
`libgcc_s.so.1` to the static archive `libgcc_s.a`. Ubuntu's
arm64 toolchain (and Debian / Raspbian arm64) **does not ship**
`libgcc_s.a` (only `libgcc_s.so.1`), so the link aborts with:
/usr/bin/ld: cannot find -lgcc_s
/usr/bin/ld: cannot find -lgcc_s (push-state / as-needed both fail)
collect2: error: ld returned 1 exit status
`ld --verbose` shows ld searching 20+ paths for `libgcc_s.a`,
finding only `libgcc_s.so` (a linker script pointing at
`libgcc_s.so.1`) which is invalid in non-PIE mode.
x86_64 Linux is unaffected because Ubuntu ships the static
`libgcc_s.a` (or a compatible static-fallback library) in its
amd64 libgcc-N-dev packaging. macOS, Windows and Cygwin go
through completely different code paths and never reach this
branch.
Extend the existing `else ifeq ($(CONFIG_HOST_MACOS),)` exclusion
to also cover HOST_ARM64 by concatenating the two variables in the
condition: `else ifeq ($(CONFIG_HOST_MACOS)$(CONFIG_HOST_ARM64),)`.
The condition is true only when both variables are empty (i.e. on
a 64-bit non-macOS non-aarch64 Linux host), so aarch64 hosts fall
through to gcc's default PIE-aware link path, which works
correctly. This concatenation idiom matches the style already
used elsewhere in the file (suggested by @xiaoxiang781216 in
review). The default text-segment placement
`-Ttext-segment=0x40000000` and `-Wl,--gc-sections` (set in the
common LDFLAGS just above this block) are honored regardless of
PIE / non-PIE.
Verified on NVIDIA Jetson Orin (Ubuntu 20.04 L4T, GCC 9.4) and
Raspberry Pi 4B (Debian 13 trixie, GCC 14.2):
$ ./build.sh sim:nsh -j$(nproc)
$ ./nuttx
NuttShell (NSH)
nsh> ostest
... [38 user_main stages, 14 PASS, 0 FAIL] ...
ostest_main: Exiting with status 0
x86_64 Linux behaviour is unchanged (the concatenation is empty
there, so the block is taken exactly as before).
Companion patch: arch/sim: rename nuttx libc memchr to avoid host
glibc collision (independent fix needed on the same aarch64 hosts).
Signed-off-by: Jinji Cui <113000688+cjj66619@users.noreply.github.com>
|
||
|---|---|---|
| .github | ||
| arch | ||
| audio | ||
| binfmt | ||
| boards | ||
| cmake | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| dummy | ||
| fs | ||
| graphics | ||
| include | ||
| libs | ||
| mm | ||
| net | ||
| openamp | ||
| pass1 | ||
| sched | ||
| syscall | ||
| tools | ||
| video | ||
| wireless | ||
| .asf.yaml | ||
| .codespell-ignore-lines | ||
| .codespellrc | ||
| .editorconfig | ||
| .gitignore | ||
| .gitmessage | ||
| .pre-commit-config.yaml | ||
| .yamllint | ||
| AUTHORS | ||
| CMakeLists.txt | ||
| CONTRIBUTING.md | ||
| INVIOLABLES.md | ||
| Kconfig | ||
| LICENSE | ||
| Makefile | ||
| NOTICE | ||
| README.md | ||
| ReleaseNotes | ||
Apache NuttX is a real-time operating system (RTOS) with an emphasis on standards compliance and small footprint. Scalable from 8-bit to 64-bit microcontroller environments, the primary governing standards in NuttX are POSIX and ANSI standards. Additional standard APIs from Unix and other common RTOSs (such as VxWorks) are adopted for functionality not available under these standards, or for functionality that is not appropriate for deeply-embedded environments (such as fork()).
For brevity, many parts of the documentation will refer to Apache NuttX as simply NuttX.
Getting Started
First time on NuttX? Read the Getting Started guide! If you don't have a board available, NuttX has its own simulator that you can run on terminal.
Documentation
You can find the current NuttX documentation on the Documentation Page.
Alternatively, you can build the documentation yourself by following the Documentation Build Instructions.
The old NuttX documentation is still available in the Apache wiki.
Supported Boards
NuttX supports a wide variety of platforms. See the full list on the Supported Platforms page.
Contributing
If you wish to contribute to the NuttX project, read the Contributing guidelines for information on Git usage, coding standard, workflow and the NuttX principles.
License
The code in this repository is under either the Apache 2 license, or a license compatible with the Apache 2 license. See the License Page for more information.