chore: pin libyulc 0.0.2 (solc 339 MiB -> 144 MiB)

[leonardoalt]

What

Bumps the pinned libyulc release from 0.0.1 to 0.0.2. Two lines in cmake/yulc.cmake.

Follow-up to #1, which merged just before this landed on that branch, so develop currently pins 0.0.1 and does not have the size reduction below.

Why

0.0.1 predated the Mathlib work in yul-compiler. Mathlib was being linked into the library because every Lean module's initializer references the initializer of each module it imports — a real symbol reference the linker cannot discard — so a single bare import Mathlib anywhere in the runtime closure pulled in all of compiled Mathlib. Narrowing those imports (powdr-labs/yul-compiler#137, powdr-labs/yul-compiler#138, powdr-labs/yul-semantics#40, all merged) took the link closure from 8,724 objects to 1,112. libyulc-v0.0.2 is cut from yul-compiler main with that in.

Measured

Rebuilt solc against each release, same tree, same flags:

	0.0.1	0.0.2	delta
solc (USE_YULC=ON)	355,502,216	219,069,328	−136.4 MB
solc (+ SOLC_STRIP_SYMBOLS=ON)	236,446,528	151,078,184	−85.4 MB
.text	185,199,409	121,448,177	−63.8 MB
.eh_frame	23,688,712	14,218,448	−9.5 MB
.rodata	8,679,320	3,982,576	−4.7 MB
defined symbols	1,001,102	570,826	−430,276

So -DUSE_YULC=ON -DSOLC_STRIP_SYMBOLS=ON now costs 144.1 MiB against a 19.4 MiB baseline solc, where #1 as merged costs 339.0 MiB.

Both binaries compile the block-rooted and object-rooted test inputs to byte-identical bytecode:

$ solc --strict-assembly --yul-backend yulc t.yul
602a5f55
$ solc --strict-assembly --yul-backend yulc obj.yul
6024600b5f3960245ff3005f3560e01c8063371303c0141561001d575060015f54015f55610022565b505f5ffd5b00

The USE_YULC=OFF default build is untouched by this.

Notes

• The release tarball shrank 242.8 MB → 211.4 MB and the bundled libyulc.so 198 MB → 79.8 MB, but libyulc.a is 759 MB, marginally larger. Expected: build-c-lib.sh archives every object under each package's build/ir, so Mathlib's objects are still in the archive — just no longer referenced, so the linker no longer pulls them.
• Reconfiguring an existing build directory across this bump needs the cached pins cleared: -UYULC_VERSION -UYULC_RELEASE_SHA256 -UYULC_LIBRARY -UYULC_HEADER.

🤖 Generated with Claude Code