Cross-build GCC 14.2.0 with --host=x86_64-montauk: the driver, cc1,
cc1plus and collect2 now link as static Montauk ET_EXEC binaries
against the hosted libstdc++, and ship in the SDK. Together with the
native binutils, TCC and the target sysroot, MontaukOS carries a
complete self-contained C and C++ toolchain at 0:/sdk.
libc: anonymous mmap/munmap over SYS_ALLOC (GCC's page allocator
wants mmap; SYS_ALLOC memory is page-aligned by construction),
getpagesize, minimal sysconf, MB_CUR_MAX, isascii/toascii, POSIX id
typedefs (ino_t, dev_t, nlink_t, ...), struct stat fields switched to
proper POSIX types (st_size is a signed off_t now), and a
conventional _STDIO_H guard marker so GMP's FILE detection works.
Build recipe and the five host-build gotchas (bundled config.subs,
gettext removal, stdio guard sniffing, endianness cache preset,
sysroot sdk symlink) are documented in toolchain/README.md. The
devkit stages the driver as gcc.elf/g++.elf/cpp.elf, the backends in
the libexec layout the driver expects, a copy of ld where collect2
searches, and a 0:/tmp scratch dir. Ramdisk: 1604 files, 368 MB.
Co-Authored-By: Claude Fable 5 <[email protected]>
The cross toolchain now builds real hosted C++: std::string, vector,
unique_ptr, iostreams and exceptions all work in a plain
x86_64-montauk-g++ invocation with no special flags. This is the
library that native cc1plus will link against for the GCC self-host.
crt1 now runs .preinit_array/.init_array before main and hooks
.fini_array through atexit (main returns via exit(), so destructors
run on both exit paths). Global constructors and libgcc's eh_frame
registration both ride this. GCC is reconfigured with
--enable-initfini-array (modern arrays instead of .ctors),
--with-newlib (satisfies libstdc++'s crossconfig for unknown hosts),
--disable-wchar_t and --disable-libstdcxx-pch; the montauk gcc patch
grows a hunk keeping os/generic ctype under --with-newlib (the
Montauk libc is not newlib).
libc additions harvested by the libstdc++ build: mbtowc/wctomb,
strxfrm, strtok/strtok_r, a real vfscanf/fscanf/scanf (character-
driven with widths and l/ll; also unblocks gprof later), fgetpos/
fsetpos/setbuf/fpos_t, modf plus the C99 float math variants
(acosf..tanhf, hypot/hypotf as wrappers), FP_* classification macros,
the full POSIX errno vocabulary, complete DT_* dirent types, and
mbstate_t.
The SDK ships the real libstdc++.a (was an empty stand-in), the C++
headers at 0:/sdk/include/c++, and cxx-test.elf (global ctor, string,
vector+sort, unique_ptr, throw/catch; exits 0 on 5/5). Ramdisk sits
at 1571 files, within the 2048 table.
Co-Authored-By: Claude Fable 5 <[email protected]>
With the TLS runtime landed (PT_TLS loading + per-thread FS base) and
tls-test.elf passing on the OS, the sysdep.h hunk that degraded BFD's
_Thread_local error state to plain globals is no longer needed.
Native binutils is rebuilt with genuine thread-locals: the shipped
tools now carry a PT_TLS segment and %fs-relative accesses, exercising
the new runtime in every invocation.
Co-Authored-By: Claude Fable 5 <[email protected]>
MontaukOS binaries could not use thread-local storage: the ELF loader
ignored PT_TLS and no FS base was ever programmed, so any %fs access
(initial-exec/local-exec TLS, e.g. libbfd's _Thread_local error state)
page faulted at address 0. This is the kernel prerequisite for
cc1plus/libstdc++ in the GCC port.
ELF loader: parse PT_TLS and build the main thread's TLS block above
the loaded image (x86-64 variant II ABI: block below the thread
pointer, TP = base + align_up(memsz, align), .tdata copied from the
template, .tbss zeroed, ABI self-pointer stored at [TP]). The
template description is kept on the process for thread spawns.
Scheduler: fsBase per thread, loaded into IA32_FS_BASE at every
dispatch site through a per-CPU cache - TLS-free processes cost one
MSR write per CPU ever, and userspace cannot desync the cache since
CR4.FSGSBASE stays off. SYS_THREAD_SPAWN gives each new thread its
own TLS block copied from the template (allocated from the process
heap; reclaimed at process teardown).
Ships tls-test.elf in the SDK (built by the devkit target): checks
.tdata values, .tbss zeroing, and the %fs:0 self-pointer, exiting
nonzero on failure. Boot-smoke verified; existing TLS-free programs
are unaffected.
Co-Authored-By: Claude Fable 5 <[email protected]>
0:/usr was a Unix transplant in an otherwise Montauk-native layout.
The SDK now lives at 0:/sdk/{bin,include,lib} (+ ldscripts under
0:/sdk/x86_64-montauk): Montauk-flavored, and a clean unit for a
future per-component installer tickbox. Native binutils is rebuilt
with --prefix=/sdk so ld's compiled-in search paths follow; future
ports configure with --prefix=/sdk.
Also add pathconf() with _PC_* names to the libc: now that realpath
exists, libiberty's lrealpath.c compiles its pathconf fallback path
unconditionally.
Shell command resolution and tab completion updated to 0:/sdk/bin.
Boot-verified in QEMU: setup, login, desktop on the new image with
zero usr/ remnants in the ramdisk.
Co-Authored-By: Claude Fable 5 <[email protected]>
Every libbfd-based native tool (objdump, as, ld, ar, nm, ...) page
faulted at startup: binutils 2.43 keeps BFD's error state in
_Thread_local variables, and MontaukOS has no TLS runtime (no FS-base
setup, no PT_TLS handling), so the %fs:0 access in bfd_init trapped at
address 0. elfedit survived only because it does not link libbfd.
Patch bfd/sysdep.h to define the TLS storage macro to empty under
__montauk__ (binutils has no fallback of its own; ac_cv_tls=none does
not even compile). Single-threaded tools lose nothing.
Confirmed on the OS: objdump -S disassembles hello.elf in the
terminal. Real TLS support (FS base + PT_TLS in the ELF loader) stays
on the roadmap for the GCC/libstdc++ milestone.
Co-Authored-By: Claude Fable 5 <[email protected]>
The devkit target in programs/GNUmakefile stages the native binutils
(as, ld, ar, nm, objcopy, objdump, readelf, ranlib, strip, size,
strings, addr2line, c++filt, elfedit as *.elf) into the image at
0:/usr/bin, plus a target-side sysroot: libc headers, montauk/ and
Api/ SDK headers and the freestanding C++ set at 0:/usr/include, and
libc.a + crt1/crti/crtn objects (with empty libm/libstdc++ stand-ins)
at 0:/usr/lib. ld's ldscripts ship under 0:/usr/x86_64-montauk.
The /usr prefix matches the binutils configure prefix, and the kernel
already resolves driveless absolute paths against the cwd drive, so
compiled-in /usr/lib search paths work natively on drive 0.
The shell resolves commands from 0:/usr/bin (after 0:/os) and tab
completion lists it. When toolchain/native/ has not been built, the
devkit step skips cleanly and the image builds as before.
Co-Authored-By: Claude Fable 5 <[email protected]>
Grow the Montauk libc enough to cross-build binutils 2.43.1 with
--host=x86_64-montauk. gas, ld, ar, nm, objcopy, objdump, readelf,
ranlib, strip and friends now link as native ET_EXEC Montauk binaries
(staged stripped in toolchain/native/, not yet shipped in the image).
New libc surface: full Linux errno and signal sets, O_* flags with
real O_EXCL/O_APPEND semantics, unlink/rmdir/dup/dup2/getpid/_exit,
kill (SYS_KILL), fcntl, fileno/fdopen, putc/getchar/rewind,
ctime/asctime, strtoll/strtoull/atoll, bsearch, mkstemp/mktemp,
realpath (lexical, drive-prefix aware), mbstowcs/mblen, chmod/fchmod/
umask/utime no-ops (VFS has no modes or settable times), full struct
stat with fake inodes, sscanf field widths (bounded conversions),
SCN*/PRI* completions, wait/waitpid over SYS_WAITPID, and new headers
sys/wait.h, sys/param.h, utime.h, wchar.h, memory.h.
fork/exec/pipe are declared but fail with ENOSYS: binutils never
spawns, and real process plumbing is the posix_spawn milestone, which
needs kernel support (exit status reporting, fd redirection).
TCC's montauk_compat.h shims (unlink, chmod, execvp, realpath, fdopen,
strtoll, strtoull) are retired in favor of the libc versions.
Co-Authored-By: Claude Fable 5 <[email protected]>
Add build-montauk-toolchain.sh: builds an OS-aware cross GCC/binutils
(same versions and prefix as the bare-metal x86_64-elf toolchain) whose
x86_64-montauk target links static ET_EXEC binaries against the Montauk
libc sysroot with no special flags: 4 KiB max page size for the kernel
ELF loader, -mno-red-zone by default, crt1/crti/crtn + -lc from the
sysroot, __montauk__ defined. Target patches are checked into
toolchain/patches/, the GCC target header into toolchain/files/.
sys/types.h now includes <stdint.h> so hosted code (libgcov and
friends) sees intptr_t via the stdio include chain.
Co-Authored-By: Claude Fable 5 <[email protected]>
danielandClaude Fable 5