# Picolibc User Guide

Contents

- [Picolibc for Hexagon: User Guide](https://docs.qualcomm.com/doc/80-N3040-23/topic/README.html)
    - [Documents](https://docs.qualcomm.com/doc/80-N3040-23/topic/README.html#documents)
    - [Which guide do I need?](https://docs.qualcomm.com/doc/80-N3040-23/topic/README.html#which-guide-do-i-need)
    - [Key flags at a glance](https://docs.qualcomm.com/doc/80-N3040-23/topic/README.html#key-flags-at-a-glance)
- [Getting Started with Picolibc on Hexagon](https://docs.qualcomm.com/doc/80-N3040-23/topic/getting-started.html)
    - [Prerequisites](https://docs.qualcomm.com/doc/80-N3040-23/topic/getting-started.html#prerequisites)
    - [Hello World: H2 target](https://docs.qualcomm.com/doc/80-N3040-23/topic/getting-started.html#hello-world-h2-target)
    - [Hello World: bare-metal with semihosting](https://docs.qualcomm.com/doc/80-N3040-23/topic/getting-started.html#hello-world-bare-metal-with-semihosting)
    - [Common errors and fixes](https://docs.qualcomm.com/doc/80-N3040-23/topic/getting-started.html#common-errors-and-fixes)
    - [Next steps](https://docs.qualcomm.com/doc/80-N3040-23/topic/getting-started.html#next-steps)
- [H2 + Picolibc Usage Guide](https://docs.qualcomm.com/doc/80-N3040-23/topic/picolibc-h2.html)
    - [Quick Reference](https://docs.qualcomm.com/doc/80-N3040-23/topic/picolibc-h2.html#quick-reference)
    - [Overview](https://docs.qualcomm.com/doc/80-N3040-23/topic/picolibc-h2.html#overview)
    - [What is H2?](https://docs.qualcomm.com/doc/80-N3040-23/topic/picolibc-h2.html#what-is-h2)
    - [First program](https://docs.qualcomm.com/doc/80-N3040-23/topic/picolibc-h2.html#first-program)
    - [Compilation and Linking](https://docs.qualcomm.com/doc/80-N3040-23/topic/picolibc-h2.html#compilation-and-linking)
    - [H2 Runtime Libraries](https://docs.qualcomm.com/doc/80-N3040-23/topic/picolibc-h2.html#h2-runtime-libraries)
    - [Memory Layout](https://docs.qualcomm.com/doc/80-N3040-23/topic/picolibc-h2.html#memory-layout)
    - [Heap Configuration](https://docs.qualcomm.com/doc/80-N3040-23/topic/picolibc-h2.html#heap-configuration)
    - [Stack Configuration](https://docs.qualcomm.com/doc/80-N3040-23/topic/picolibc-h2.html#stack-configuration)
    - [Thread-Local Storage (TLS)](https://docs.qualcomm.com/doc/80-N3040-23/topic/picolibc-h2.html#thread-local-storage-tls)
    - [Entry Point and Startup](https://docs.qualcomm.com/doc/80-N3040-23/topic/picolibc-h2.html#entry-point-and-startup)
    - [BSS and Data Initialization](https://docs.qualcomm.com/doc/80-N3040-23/topic/picolibc-h2.html#bss-and-data-initialization)
    - [Complete Example](https://docs.qualcomm.com/doc/80-N3040-23/topic/picolibc-h2.html#complete-example)
    - [Troubleshooting](https://docs.qualcomm.com/doc/80-N3040-23/topic/picolibc-h2.html#troubleshooting)
    - [Summary](https://docs.qualcomm.com/doc/80-N3040-23/topic/picolibc-h2.html#summary)
    - [Related Documentation](https://docs.qualcomm.com/doc/80-N3040-23/topic/picolibc-h2.html#related-documentation)
    - [References](https://docs.qualcomm.com/doc/80-N3040-23/topic/picolibc-h2.html#references)
- [Bare-Metal Hexagon with Picolibc](https://docs.qualcomm.com/doc/80-N3040-23/topic/picolibc-baremetal.html)
    - [Overview](https://docs.qualcomm.com/doc/80-N3040-23/topic/picolibc-baremetal.html#overview)
    - [Minimal compile command](https://docs.qualcomm.com/doc/80-N3040-23/topic/picolibc-baremetal.html#minimal-compile-command)
    - [Memory layout and linker scripts](https://docs.qualcomm.com/doc/80-N3040-23/topic/picolibc-baremetal.html#memory-layout-and-linker-scripts)
    - [Semihosting (QEMU-hosted I/O)](https://docs.qualcomm.com/doc/80-N3040-23/topic/picolibc-baremetal.html#semihosting-qemu-hosted-i-o)
    - [No-semihosting: stub I/O for production](https://docs.qualcomm.com/doc/80-N3040-23/topic/picolibc-baremetal.html#no-semihosting-stub-i-o-for-production)
    - [Heap configuration](https://docs.qualcomm.com/doc/80-N3040-23/topic/picolibc-baremetal.html#heap-configuration)
    - [Stack configuration](https://docs.qualcomm.com/doc/80-N3040-23/topic/picolibc-baremetal.html#stack-configuration)
    - [Building without the C standard library (fully standalone)](https://docs.qualcomm.com/doc/80-N3040-23/topic/picolibc-baremetal.html#building-without-the-c-standard-library-fully-standalone)
    - [Worked example: semihosting file I/O](https://docs.qualcomm.com/doc/80-N3040-23/topic/picolibc-baremetal.html#worked-example-semihosting-file-i-o)
    - [Troubleshooting](https://docs.qualcomm.com/doc/80-N3040-23/topic/picolibc-baremetal.html#troubleshooting)
    - [POSIX and Syscall Coverage on Bare-Metal](https://docs.qualcomm.com/doc/80-N3040-23/topic/picolibc-baremetal.html#posix-and-syscall-coverage-on-bare-metal)
    - [Related documentation](https://docs.qualcomm.com/doc/80-N3040-23/topic/picolibc-baremetal.html#related-documentation)
- [Semihosting Support for Hexagon](https://docs.qualcomm.com/doc/80-N3040-23/topic/semihosting.html)
    - [Overview](https://docs.qualcomm.com/doc/80-N3040-23/topic/semihosting.html#overview)
    - [Architecture](https://docs.qualcomm.com/doc/80-N3040-23/topic/semihosting.html#architecture)
    - [System Calls](https://docs.qualcomm.com/doc/80-N3040-23/topic/semihosting.html#system-calls)
    - [Error Handling](https://docs.qualcomm.com/doc/80-N3040-23/topic/semihosting.html#error-handling)
    - [Implementation Details](https://docs.qualcomm.com/doc/80-N3040-23/topic/semihosting.html#implementation-details)
    - [Standard I/O](https://docs.qualcomm.com/doc/80-N3040-23/topic/semihosting.html#standard-i-o)
    - [QEMU Configuration](https://docs.qualcomm.com/doc/80-N3040-23/topic/semihosting.html#qemu-configuration)
    - [Limitations](https://docs.qualcomm.com/doc/80-N3040-23/topic/semihosting.html#limitations)
    - [Debugging](https://docs.qualcomm.com/doc/80-N3040-23/topic/semihosting.html#debugging)
    - [Testing](https://docs.qualcomm.com/doc/80-N3040-23/topic/semihosting.html#testing)
    - [API Reference](https://docs.qualcomm.com/doc/80-N3040-23/topic/semihosting.html#api-reference)
    - [Next Steps](https://docs.qualcomm.com/doc/80-N3040-23/topic/semihosting.html#next-steps)

Last Published: Oct 06, 2026

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