[priyanshrv-netizen]

What

Exports _Flt (+SeQg8c1WC0), _Dbl (e+hi-tOrDZU) and _Ldbl (43u-nm1hQc8), the tables behind Dinkumware's float.h macros, which the system libc.prx (build J03093718) exports and no source in core/libs/prx or open pull request defines yet.

Each table is 80 bytes, read from that module's data: six ints (digits, mantissa digits, maximum and minimum decimal exponent, maximum and minimum binary exponent), 8 bytes of zero padding, then epsilon, maximum and minimum as 16-byte _Dconst values:

Table	Integers	Epsilon	Maximum	Minimum
_Flt	6, 24, 38, 128, -37, -125	0x34000000	0x7f7fffff	0x00800000
_Dbl	15, 53, 308, 1024, -307, -1021	0x3cb0000000000000	0x7fefffffffffffff	0x0010000000000000
_Ldbl	18, 64, 4932, 16384, -4931, -16381	2^-63	x87 maximum	x87 minimum normal

_Ldbl describes the x87 80-bit format, as Sony's long double is. They go in core/libs/prx/libc/src/Math.cpp as DinkumwareFloatCharacteristics, in a spot away from the lines #6085 and #8570 change.

CheckDinkumwareFloatCharacteristics in core/libs/tests/GuestMath.cpp checks the layout, the integers against <cfloat> (the x87 values for _Ldbl), the three values against std::numeric_limits with their unused bytes zero, and the zero padding.

Tested

Windows 10, MSYS2 MinGW-w64 GCC 15.2.0 (mingw64, not the WinLibs UCRT toolchain from BUILD.md). I did not configure the full CMake build. Math.cpp builds with -Wall -Wextra -Werror -fno-asynchronous-unwind-tables, and GuestMath.cpp compiles without warnings. CheckDinkumwareFloatCharacteristics (copied unchanged from GuestMath.cpp) compiled against this Math.cpp passes; against main's Math.cpp it fails to link on all three symbols.

Against the console's own data: I mapped that libc.prx's segments into memory, applied its relocations and compared the three tables with the objects the module exports under the same NIDs. All 80 bytes are identical for each.

tools/check_conventions.py --base origin/main passes. tools/pr_overlap.py --branch feat/libc-float-characteristics reports no overlap. It could not compare #6044, #6158 and #7201 (each conflicts with main); I checked them by hand: #6044 only renames GuestMath.cpp, and #6158 and #7201 change other lines of these files and add none of these exports. Not tested on Linux; no title was run.

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
• Fixes: none
• Unblocks: none
• GPUs tested: n/a
• AI-assisted: yes

🤖 Generated with Claude Code

[github-actions]

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/GuestMath.cpp
PR 6158	core/libs/prx/libc/src/Math.cpp core/libs/tests/GuestMath.cpp
PR 6879	core/libs/prx/libc/src/Math.cpp
PR 7201	core/libs/prx/libc/src/Math.cpp
PR 8449	core/libs/prx/libc/src/Math.cpp core/libs/tests/GuestMath.cpp
PR 8658	core/libs/prx/libc/src/Math.cpp core/libs/tests/GuestMath.cpp