Well, you are right, you can’t. At least not directly. This is well documented in many projects relying on interposing binaries, like faketime. But what if we could write something that would take a static binary, replace at least the direct syscalls with ones going through libc and load it with the dynamic linker? We are in luck, because the excellent QEMU project has a user space emulator! It can be compiled as a dynamically linked executable, honors LD_PRELOAD and uses the host libc’s syscall – well, at least sometimes. Sometimes syscalls just bypass libc. The missing piece was a way to make QEMU always take the interposable path and call the host libc instead of using an arch-specifix assembly routine (`safe_syscall_base`) to construct the syscall and going directly to the kernel. Luckily, this turned out to be doable. A small patch later, QEMU gained a switch that forces all syscalls through libc. Suddenly, our static binaries started looking a lot more dynamic! $ faketime '2008-12-24 08:15:42' qemu-x86_64 ./test_static_clock_gettime 2008-12-24 08:15:42.725404654 $ file test_static_clock_gettime test_clock_gettime: ELF 64-bit LSB executable, x86-64, version 1 (GNU/Linux), statically linked, ... With this in place, Firebuild can finally wrap even those secretive statically linked tools. QEMU runs them, libc catches their syscalls, `LD_PRELOAD` injects `libfirebuild.so`, and from there the usual interposition magic happens. The result: previously uncachable build steps can now be traced, cached, and shortcut just like their dynamic friends. There is one more problem though. Why would the static binaries deep in the build be run by QEMU? Firebuild also intercepts the `exec()` calls and now it rewrites them on the fly whenever the executed binary would be statically linked! $ firebuild -d comm bash -c ./test_static ... FIREBUILD: fd 9.1: ({ExecedProcess 161077.1, running, "bash -c ./test_static", fds=[0: {FileFD ofd={FileO FD #0 type=FD_PIPE_IN r} cloexec=false}, 1: {FileFD ofd={FileOFD #3 type=FD_PIPE_OUT w} {Pipe #0} close_o n_popen=false cloexec=false}, 2: {FileFD ofd={FileOFD #4 type=FD_PIPE_OUT w} {Pipe #1} close_on_popen=fal se cloexec=false}, 3: {FileFD NULL} /* times 2 */]}) { "[FBBCOMM_TAG]": "exec", "file": "test_static", "// fd": null, "// dirfd": null, "arg": [ "./test_static" ], "env": [ "SHELL=/bin/bash", ... "FB_SOCKET=/tmp/firebuild.cpMn75/socket", "_=./test_static" ], "with_p": false, "// path": null, "utime_u": 0, "stime_u": 1017 } FIREBUILD: -> proc_ic_msg() (message_processor.cc:782) proc={ExecedProcess 161077.1, running, "bash -c ./test_static", fds=[0: {FileFD ofd={FileOFD #0 type=FD_PIPE_IN r} cloexec=false}, 1: {FileFD ofd={FileOF D #3 type=FD_PIPE_OUT w} {Pipe #0} close_on_popen=false cloexec=false}, 2: {FileFD ofd={FileOFD #4 type=F D_PIPE_OUT w} {Pipe #1} close_on_popen=false cloexec=false}, 3: {FileFD NULL} /* times 2 */]}, fd_conn=9. 1, tag=exec, ack_num=0 FIREBUILD: -> send_fbb() (utils.cc:292) conn=9.1, ack_num=0 fd_count=0 Sending message with ancillary fds []: { "[FBBCOMM_TAG]": "rewritten_args", "arg": [ "/usr/bin/qemu-user-interposable", "-libc-syscalls", "./test_static" ], "path": "/usr/bin/qemu-user-interposable" } ... FIREBUILD: -> accept_ic_conn() (firebuild.cc:139) listener=6 ... FIREBUILD: fd 9.2: ({Process NULL}) { "[FBBCOMM_TAG]": "scproc_query", "pid": 161077, "ppid": 161073, "cwd": "/home/rbalint/projects/firebuild/test", "arg": [ "/usr/bin/qemu-user-interposable", "-libc-syscalls", "./test_static" ], "env_var": [ "CCACHE_DISABLE=1", ... "SHELL=/bin/bash", "SHLVL=0", "_=./test_static" ], "umask": "0002", "jobserver_fds": [], "// jobserver_fifo": null, "executable": "/usr/bin/qemu-user-interposable", "// executed_path": null, "// original_executed_path": null, "libs": [ "/lib/x86_64-linux-gnu/libatomic.so.1", "/lib/x86_64-linux-gnu/libc.so.6", "/lib/x86_64-linux-gnu/libglib-2.0.so.0", "/lib/x86_64-linux-gnu/libm.so.6", "/lib/x86_64-linux-gnu/libpcre2-8.so.0", "/lib64/ld-linux-x86-64.so.2" ], "version": "0.8.5.1" } The QEMU patch is forwarded to qemu-devel. If it lands, anyone using QEMU user-mode emulation could benefit — not just Firebuild. For Firebuild users, though, the impact is immediate. Toolchains that mix dynamic and static helpers? Cross-builds that pull in odd little statically linked utilities? Previously “invisible” steps in your builds? All now fair game for caching. Firebuild 0.8.5 ships this new capability out of the box. Just update, make sure you’re using a patched QEMU, and enjoy the feeling of watching even static binaries fall neatly into place in your cached build graph. Ubuntu users can get the prebuilt patched QEMU packages from the Firebuild PPA already. Static binaries, welcome to the party!

A proposal to standardise on using an /llms.txt file to provide information to help LLMs use a website at inference time.

# 39th E.S.PKU Conference 2025 Hosted at **University Hospital Hamburg Eppendorf (UKE)** Please do not book hotel rooms individually. Conference access will most likely only be availabe to people booking the conference package. Day tickets will likely not be available this year! ## Agenda Highlights: * * * **Programme for all attendees (Common Programme):** * Experiences with PKU in Germany * Experiences with Sepiapterin and Pegvaliase in Germany * European PKU Guidelines 2.0 * Do we speak the same language? Pros and Cons of European and German Guidelines * New dietetic and drug treatments – what should they bring to the patients? * What can national patients’ organisations do to get drugs approved? * What can we learn from the transition process in Leipzig * Phe Free Consortium: How does it work and what’s in it for the patient? * Patients’ voices recorded in a scientific approach * Sheila Jones Award **Programme for Patients and their families (Patients’ Programme):** * Mental Health in PKU: From impact of diagnosis to uncertainties in health perspectives – What do we know? * Shared Decision Making: The role of patients’ preferences in therapeutic decisions * Should patients participate in clinical trials – and why? _**Common and Patients’ programmes will be simultaneously translated (English <> German)**_ **Programme for Researchers and Health Care Providers (Professionals’ Programme):** * The Phe Free Consortium Neurocognitive Work: What can we learn from it? * MRI and neuropsychological data after four weeks increased Phe intake * The French studies in adults – can Europe learn from it? * After 30 years of gene therapy studies – what can professionals and patients expect? * Do we need to treat everyone with a blood Phe above 360 µmol/l? * * * ## Conference Hotel * * * _Hotels will be assigned prior to the conference. It's not possible to choose the hotel. Please do not book a hotel indivudally, conference access is only available as a package (including accomodation)._ * **Dorint Hotel Hamburg Eppendorf **(direct neighbor to conference venue) * **Motel One Hamburg Altona **(approximately 3.5 km from the venue) Bus transfer once a day provided ## Newsletter E.S.PKU Conference Newsletter E-Mail Address * Subscribe to E.S.PKU conference newsletter Yes, please subscribe me Please verify that you are not a spam bot If you are human, leave this field blank. Δ ## Get more info ... __ E.S.PKU Conference? __ Get all the information Learn more about the conference * * * __ Rewind 2024 ... __ E.S.PKU Conference 2024 Revisit last years conference * * * ## Registration Procedure * * * * **Step 1: Please fill in the registration form on the E.S.PKU Website (****espku.org****) as soon as possible. ** You will immediately receive an e-mail with an attached spreadsheet for further details. * **Step 2: Please complete and return the spreadsheet within 7 days. ** Upon registration you will receive a mail confirmation that and a spreadsheet to fill out information for each participant booked by you. Please fill out and return the spreadsheet within 7 days. Within a few days you will also receive a invoice for your registration. Bookings are only valid once we have confirmed the money has been received. * **Step 3: Please pay the registration fee as indicated in the notification. ** Once your payment has arrived, you will receive a confirmation of registration. **Registration deadline:** Registrations will be accepted until the conference is sold out. _Please note: A limited number of day tickets may or may not be available later, depending on conference capacities being available. However, we do expect the conference to sold out rather sooner than later, so it is very possible hat there are no day tickets available this year._ _Please contact us (form below) if you still have got questions or want to come as a family with younger children._ __ Register Now ## Still got questions? * * *

We need to talk about your Github addiction par Ploum - Lionel Dricot.