Version 0.8.31-pre.1

Changelog

Language Features:

• Yul: Introduce builtin clz(x) for counting the number of leading zero bits in a 256-bit word.

Compiler Features:

• ethdebug: Experimental support for instructions and source locations under EOF.

Bugfixes:

• Assembler: Fix not using a fixed-width type for IDs being assigned to subassemblies nested more than one level away, resulting in inconsistent --asm-json output between target architectures.
• Yul Optimizer: Fix edge case in which invalid Yul code is produced by ExpressionSimplifier due to expressions being substituted that contain out-of-scope variables.

Build System:

• Update minimum version requirements of Boost to 1.83.0 for non-windows builds and of GCC and Clang to 13.3 and 18.1.3, respectively. Fixes infinite recursion on boost::rational comparison affecting compiler binaries built with GCC<14.0 and Boost<1.75.