[matthias-kleiner]

…tom streamer

The custom member streamer for CalArray::mData writes the count N/2 followed by N single shorts, but reads N/2 ints and reinterprets each as a pair of flags (the layout written by ROOT < 6.33). Every object written by the streamer itself (ROOT >= 6.33) therefore comes back with each pair of adjacent pads swapped. This affects all IDC_PadStatusMap objects written since the streamer was introduced (e.g. 2026 data, ROOT 6.36.04): the dead channel map used in reconstruction marks the neighbour of an isolated bad pad instead of the pad itself. Objects written with ROOT < 6.33 (e.g. 2025, ROOT 6.32.06) are read correctly.

The class version did not change, so the reader now selects the layout by the ROOT version that wrote the buffer (TBuffer::GetVersionOwner(); the current ROOT if the buffer has no file): < 6.33 as before, >= 6.33 N shorts. The writer is unchanged, so existing objects stay readable and no re-upload is needed.

Add a ROOT I/O round-trip unit test for CalDet, which fails with the old reader (349440 of 524160 flags differ) and passes with the new one.

[alibuild]

Error while checking build/O2/fullCI_slc9 for e4426e4 at 2026-11-14 12:43:

## sw/BUILD/O2-sim-challenge-test-latest/log
./sim-challenge.log[ERROR] SHUTTING DOWN DUE TO SIGNALED EXIT IN COMPONENT 208
./sim-challenge.log[12:43:12][ERROR] Some error/interrupt occurred on socket during receive
./sim.log[ERROR] SHUTTING DOWN DUE TO SIGNALED EXIT IN COMPONENT 208
./sim.log[12:43:12][ERROR] Some error/interrupt occurred on socket during receive


## sw/BUILD/o2checkcode-latest/log
--
========== List of errors found ==========
++ echo 'Found 0 errors and 0 warnings.'
Found 0 errors and 0 warnings.
++ [[ 0 -gt 0 ]]
++ [[ 0 -gt 0 ]]
++ [[ 0 -gt 0 ]]
++ mkdir -p /sw/INSTALLROOT/972e3dbce16c8cacf06a769e117521a56b4d28c6/slc9_x86-64/o2checkcode/1.0-local58/etc/modulefiles
++ alibuild-generate-module
+ HAS_BIN=
+ HAS_LIB=
+ HAS_CMAKE=
+ HAS_ROOT=
+ '[' 0 '!=' 0 ']'
+ cat
+ printf 'if ![ is-loaded '\''BASE/1.0'\'' ] {\n module load BASE/1.0\n}'
+ echo 'BUILD_REQUIRES=CMake alibuild-recipe-tools defaults-release'
BUILD_REQUIRES=CMake alibuild-recipe-tools defaults-release
+ FULL_BUILD_REQUIRES='googlebenchmark pytorch_cpuinfo ninja-fortran O2-customization defaults-release FairCMakeModules Alice-GRID-Utils MPFR alibuild-recipe-tools date json-c bz2 ninja double-conversion CMake UUID Python-modules-list safe_int'
+ echo 'FULL_BUILD_REQUIRES=googlebenchmark pytorch_cpuinfo ninja-fortran O2-customization defaults-release FairCMakeModules Alice-GRID-Utils MPFR alibuild-recipe-tools date json-c bz2 ninja double-conversion CMake UUID Python-modules-list safe_int'
FULL_BUILD_REQUIRES=googlebenchmark pytorch_cpuinfo ninja-fortran O2-customization defaults-release FairCMakeModules Alice-GRID-Utils MPFR alibuild-recipe-tools date json-c bz2 ninja double-conversion CMake UUID Python-modules-list safe_int
++ env
++ cut -f1 -d=
++ grep -v '^DEFAULT_'
++ grep -v PKGREVISION
++ grep -v ALIBUILD_RECIPE_TOOLS
++ grep REVISION
++ sed -e s/_REVISION//
+ for x in $(env | cut -f1 -d= | grep -v "^DEFAULT_" | grep -v PKGREVISION | grep -v ALIBUILD_RECIPE_TOOLS | grep REVISION | sed -e 's/_REVISION//')
++ eval 'echo $LIBFFI_REVISION'
+++ echo 14
+ REVISION_VALUE=14
++ eval 'echo $LIBFFI_VERSION'
+++ echo v3.2.1-alice1
+ VERSION_VALUE=v3.2.1-alice1
++ eval 'echo $LIBFFI_ROOT'
+++ echo /sw/slc9_x86-64/libffi/v3.2.1-alice1-14
+ ROOT_PATH_VALUE=/sw/slc9_x86-64/libffi/v3.2.1-alice1-14
+ '[' -z 14 ']'
+ echo 'googlebenchmark pytorch_cpuinfo ninja-fortran O2-customization defaults-release FairCMakeModules Alice-GRID-Utils MPFR alibuild-recipe-tools date json-c bz2 ninja double-conversion CMake UUID Python-modules-list safe_int'
+ tr '[:lower:]' '[:upper:]'
[0 more errors; see full log]

Full log here.