Optimizing code size is crucial for mobile applications, and function merging is a key technique to achieve this by consolidating identical or similar functions. Recent advancements in global function merging and identical code folding (ICF) at link time have resulted in significant size reductions, with a 3% reduction on top of the state-of-the-art global outliner and affecting 15% of total functions. Additionally, a new safe_thunks mode has been introduced to improve binary size reduction without compromising runtime safety, achieving an additional 0.45% size savings over regular safe ICF. However, function merging poses challenges for symbolication, which have been addressed through enhancements such as a new DWARF attribute and extended GSYM format support, laying the groundwork for more accurate symbolication in optimized binaries.