Every library under core/libs/prx links the libc and libkernel import
libraries, and every NID patch step depended on the unpatched libc.prx.
GNU ld 2.46 rewrites the import library on every link with new archive
timestamps (the member headers and the symbol map header), so the restat
on the link edge never pruned anything: one libc or libkernel .cpp edit
relinked all 124 libraries and re-patched all of them.
On MinGW the shared library link now writes the import library to
<implib>.new with SOURCE_DATE_EPOCH=0 (ld then writes zero member
timestamps), makes the symbol map deterministic with ranlib -D and copies
the result over the import library only when its bytes differ
(cmake -E copy_if_different). The link edge keeps restat, so a link that
keeps the exports leaves the import library untouched and prunes every
dependent link. The SOURCE_DATE_EPOCH also zeroes the export directory
TimeDateStamp of the DLL; the COFF header TimeDateStamp that the unwinder
keys on is unchanged.
The NID patch steps only use the names libc exports. nid_patcher
--write-export-list writes those names, normalized and sorted, to
libc.exports and leaves the file untouched when they did not change; the
patch steps read it with --preserve-export-list and depend on it instead
of libc.prx, on every platform. A patched library is byte-identical to
one patched against libc.prx.
Measured on Windows (GCC 15.2, -j 4, loaded machine) after touching
libc/src/Strings.cpp: with CMAKE_LINK_DEPENDS_NO_SHARED off, 124 links and
124 patches in 74.9 s before, 1 compile, 1 link, the export list and the
libc patch in 4.3 s after; with it on, 124 patches in 7.8 s before and
the same four steps in 5.3 s after. Touching libkernel/Time/Time.cpp
runs 123 links and 123 patches (89.1 s) before and one compile, link and
patch (3.4 s) after. Removing a libc export still relinks and re-patches
all 124 libraries.
nid_patcher_macho covers --write-export-list (sorted normalized names, no
rewrite when unchanged, rewrite when changed) and --preserve-export-list
(the same exports kept as with --preserve-exports; malformed lists and
two references refused). It fails on main, where the option is unknown.
Sources: SOURCE_DATE_EPOCH, https://reproducible-builds.org/specs/source-date-epoch/;
ranlib -D and ld --out-implib, GNU binutils documentation; ninja restat,
https://ninja-build.org/manual.html#ref_rule.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
nid_patcher turns the _nid_postfix names of a library into NIDs for ELF
and PE. A library built on macOS is a Mach-O dylib, whose exports are in
a dyld export trie and whose imports are in the chained fixups, so it
gets its own patcher.
- The export trie is read, every exported C name (without Mach-O's
leading underscore) is resolved to its NID, and the trie is rebuilt the
way ld64 lays it out: the offsets are uleb128, so the layout is repeated
until it is stable. A trie that no longer fits is appended to
__LINKEDIT, which has to end the file, and a signed image is refused.
- Weak definitions that are not marked _nid_postfix or _nid_no_patch keep
their names: dyld coalesces those across images by name.
- In the chained imports, names bound to a .prx dylib that are guest
facing (a _nid_postfix name or an sce prefix) are patched in place; a
name that would grow, or that shares storage with another import, is an
error. Images that use bind opcodes instead of chained fixups are
refused.
- ExportExclusions reads the exports of a reference Mach-O, so the
exclusion list works for libraries built on macOS as well.
The patcher rewrites .dynstr in place and reorders .dynsym for
.gnu.hash, but .gnu.version_d kept pointing at name offsets that the
rewrite had recycled: a library carrying symbol version definitions
came out with renamed or blanked version names while its symbols
still advertised a version.
No library in the build defines symbol versions, so fail on
.gnu.version_d during the section scan and leave the input untouched
instead of carrying version remapping that nothing exercises. The
test covers the rejection and that a library without version
definitions is still patched.
Co-authored-by: arena-agent <297053741+arena-agent@users.noreply.github.com>
The NID patcher rebuilds .dynstr keeping only the DT_NEEDED and
DT_SONAME strings, so DT_RUNPATH kept a stale offset and the patched
libraries shipped with an empty runpath. A library could then load only
those sibling prx that the executable already loads itself:
libSceVideoOut.prx needs libSceKeyboard.prx, which a title that does
not import libSceKeyboard never loads, so it fails at startup.
The patcher now keeps DT_RPATH and DT_RUNPATH strings, and the prx
libraries are linked with a $ORIGIN runpath instead of the build
directory, so they find each other wherever they are copied.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
libSceSysmodule/Export.cpp parsed /proc/self/maps device major/minor
numbers into signed int with a %x format, which is undefined behaviour
per the C standard even though it happened to work on this target;
switched to unsigned int to match the format specifier.
NidPatcherUtils.hpp's StripNidPostfix built a truncated copy with
substr(0, n) where the prefix is already the string itself; resize(n)
does the same truncation without the extra allocation and copy.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
