014ea57042
The ET_DYN path computes run-time addresses from link-time ones in five places, each open-coding the arithmetic, and two of them disagree about how: libelf_relocatedyn() adds textalloc to a relocation's r_offset in one branch and subtracts datasec before adding datastart in the next, while the value translation a few lines further down picks between those two forms with an explicit test on datasec. Collect that into libelf_addr(), which makes the test once: an address below the data segment's link-time base belongs to text, anything at or above it to data. This changes nothing today. libelf_elfsize() sets segpad = datasec - (text_vaddr + textsize) and libelf_load() then places datastart = textalloc + textsize + segpad so datastart - datasec is textalloc, and the data branch reduces to textalloc + vaddr -- exactly what the text branch returns, and exactly what adding a single load bias did before. The two forms are the same arithmetic written twice. They stop being the same once text and data are placed independently, which is what an FDPIC object requires: its two PT_LOAD segments are relocated separately so that the read-only one can be mapped in place on the media while only the writable one is copied. Having the translation in one function is what makes that possible without auditing every open-coded expression again. Built for mps3-an547:picostest, which is CONFIG_ELF with CONFIG_PIC, and boots identically to the same configuration without this change. Assisted-by: Claude Opus 5 (1M context) <noreply@anthropic.com> Signed-off-by: Marco Casaroli <marco.casaroli@gmail.com> |
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| 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 | ||
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| .pre-commit-config.yaml | ||
| .yamllint | ||
| AUTHORS | ||
| CMakeLists.txt | ||
| CONTRIBUTING.md | ||
| INVIOLABLES.md | ||
| Kconfig | ||
| LICENSE | ||
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| 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.