feat(libc): export std::setw(int)

[Mouad-Scriptz-0]

What

Exports std::setw(int) (_ZSt4setwi) from libc. Sony's libc is Dinkumware, where setw returns a manipulator that holds a function pointer and the width (16 bytes, returned in RAX:RDX); the caller invokes the pointer with the stream's ios_base and the width. The returned function stores the width in the stream's ios_base (GuestLocale::IosBase::width, offset 0x20) and returns the stream, leaving flags and precision alone; a null stream throws. The call convention comes from the title's own call site (mov esi, edx; call rax), and flags at 0x18 in that code matches the existing IosBase layout.

PPSA21402 imports setw and no library exported it: tools/import_audit.py lists it as the title's only absent import, and reports 0 absent with this change.

Tested

Fedora 44 (kernel 7.2.8, GCC 16.2.1, Ninja, Release, BUILD_TESTING=ON, Intel Arc Meteor Lake, Mesa 26.2.3), worktree on main e16b2bc: guest_locale passes with the new CheckStreamWidth (the pair is returned, the returned function sets the width and returns the same stream, flags and precision and the bytes around the object stay untouched, a null stream throws); without the export the test does not link. The title (PPSA21402) starts and renders with the patched libc.prx. It later stops with null or misaligned index base from the graphics path, which it also does with the previous libc.prx, so it is not related to this change. Not tested on Windows.

Checklist

• Based on current main; no other open PR implements the same functions
• One topic per PR; follow-ups go in a new PR
• No comments in code except technical debt
• Unimplemented paths throw (NotImplemented_nid_no_patch); silent stubs are listed under Silent stubs in their library's technical debt file
• No notes, investigation .md files or images added to the repository (attach them to this PR)
• New third-party code is a submodule built from source
• Generic behaviour, not specific to one title
• Depends on: none
• Unblocks: PPSA21402 (no Game bring-up discussion yet)
• GPUs tested: n/a (libc only)
• AI-assisted: yes (Claude Code)

🤖 Generated with Claude Code

[github-actions]

Progress report (31cbb55 → 2e86b69)

➖ System libraries: 88.83% (+0.0%, +2 implemented functions)

✅ 2 implemented

Library	Name
libc	SetStreamWidth
libc	_ZSt4setwi_nid_postfix

[github-actions]

Other open pull requests touch the same code. Merging one will break the other, or both implement the same thing. If this one builds on them, list them in Depends on.

Pull request	Conflicting files (lines on main)	Same exports	Same new files
PR 6975	core/libs/prx/libc/src/LocaleSupport.cpp L309 core/libs/tests/GuestLocale.cpp L21, L154, L182

Some comparisons could not be completed because a pull request conflicts with the base branch. Review these shared files manually before concluding that there is no overlap.

Pull request	Shared files not compared
PR 6044	core/libs/tests/GuestLocale.cpp
PR 7081	core/libs/prx/libc/src/LocaleSupport.cpp

[johnmaia]

Windows run, since Windows is untested. Windows 11, WinLibs GCC 15.2.0 r7 (MinGW), Release, BUILD_TESTING=ON, RTX 4080, ctest -j4 --timeout 300. Head 2e86b69 merged into main 5d9dcc4, plus #6452 so the MinGW test build works.

• guest_locale passes.
• The full suite passes 1299 of 1300. The only failure, in all three PR runs of this batch, is guest_kqueue ("the vnode watch error lacks "parent""). An elevated session holds the backup privilege, which bypasses the denied-parent case; test(libkernel): drop backup privileges in denied parent watch #6599, fix(tests): drop backup privileges for denied parent watch #6629 and test(libkernel): deny the kqueue parent listing to the token user's SID #6173 address that test, and it is unrelated to this change.

Not tested: a negative control on Windows.

AI-assisted: yes (Claude Code)