Bug Fixes

• Ensure forward compatibility of package hashing with the upcoming Python 3.14 release. (#51042)
• The spack diff command now shows differences in runtime dependencies (e.g., gcc-runtime, glibc), which were previously hidden. (#51076)
• Fix a regression where the solver would mishandle a compiler that was required as both a build and a link dependency. (#51074)
• Resolved issues with selecting external packages that have a specific compiler specified. (#51064)
• Fix a bug where the concretizer would compute solution scores incorrectly when the package does not depend on a compiler. (#51037)
• The solver now correctly evaluates and respects package requirements that specify a hash. (#51065)
• Fix an issue where sparse checkouts for different packages could overwrite each other in a source cache or mirror. (#51080)
• Prevent spack repo add from overwriting the default branch when initially cloning a repository. (#51105)
• Add exception handling for bad URLs when fetching git provenance information. (#51022)
• Spack no longer conflates git warning messages with command output. (#51045)
• Fix an issue with non-path-based package repositories in environments. (#51055)
• Spack now validates the terminal size and will fall back to LINES and COLUMNS environment variables if detection fails. (#51090)
• Fix an issue where the package's fetcher was not being set correctly. (#51108)
• Ensure spack tutorial clones Spack v1.0 instead of v0.23. (#51091)

Enhancements

• Various improvements to the documentation (#51014, #51033, #51039, #51049, #51066, #51073, #51079, #51082, #51083, #51086, #51126, #51131, #51132, #51025)