This is the first patch of the 6.40 release series. A few items were addressed: see list below.

Items addressed for this release

The following items were addressed:

• #22538 - [ntuple] Late model extension of untyped records broken
• #22496 - root -q -e '.gh bug' doesn't work on ssh connections
• #22471 - issue with transparency and interactive mode on macOS
• #22447 - 6.40: Glitch in TTree::Draw for 3D (missing bins)
• #22436 - [tmva][sofie] MaxPool and AveragePool generates wrong code for asymmetric padding
• #22427 - Failing ML Dataloader test on alma10 builds with auto-registration off
• #22417 - 6.40: TBox added to TH1::GetListOfFunctions() appears to be freed before Write
• #22415 - [ftgl] FTGL builtin build fails due to missing src/FTLibrary.h
• #22414 - TFileMerger: when using kOnlyListed, any 'listed' key will bring in any unlisted keys that are a suffix of a listed key
• #22396 - Crash in PyROOT in 6.40 (GIL issue?)
• #22395 - TGeoTessellated volumes read from GDML impossible to be closed (6.40.00 regression)
• #22394 - Unable to build ROOT 6.40 against free-threaded python 3.14t (6.40.00 regression)
• #22378 - SetOSX_SDK.cmake overrides requested CMAKE_OSX_SYSROOT
• #22370 - ROOT 6.40.00 seems won't compile with Clang + GCC 16 standard library
• #22367 - Wrong interaction of DefinePerSample with downstream varied action
• #22300 - Compilation failure with Ubuntu 26.04

Versions of built-in packages

The version of the following packages has been updated:

• xrootd: 5.9.5