gnatprove bug related to Ada Util Log Rolling File Appender

Dear Sir or Madam,

you will find below a bug report of gnatprove, used on a progam.
It seems to be related to Ada Util Logger Rolling File Appender.

Below the alire.tom

name = "investments"
description = "investments"
version = "0.1.0-dev"

authors = ["odavy"]
maintainers = ["odavy olivier.davy@gmail.com"]
licenses = "MIT OR Apache-2.0 WITH LLVM-exception"
website = ""
tags = []

executables = ["investments"]

[[depends-on]]
gnatprove = "^16.1.0"

[[depends-on]]
gnatcov = "^26.2.1"

[[depends-on]]
utilada = "^2.9.0"

[[depends-on]]
ado = "^2.5.0"

[[depends-on]]
ado_postgresql = "^2.5.0"

[[depends-on]]
utilada_curl = "^2.9.0"

[[depends-on]]
aunit = "^26.0.0"

[[depends-on]]
gnattest_bin = "^26.2.0"

[[depends-on]]
gnatcoll = "^26.0.0"

[[depends-on]]
gnatcoll_sql = "^26.0.0"

[[depends-on]]
gnatcoll_postgres = "^26.0.0"

Below the bug report

PS W:\01-odavy\devel\ada\investments> alr gnatprove
Phase 1 of 3: generation of data representation information ...
Phase 2 of 3: generation of Global contracts ...
+===========================GNAT BUG DETECTED==============================+
| 1.0 (spark) Program_Error spark_util-types.adb:2367 explicit raise |
| Error detected at util-log-appenders-rolling_files.ads:75:4 |
| Compiling C:\Users\DAVYO\AppData\Local\alire\cache\builds\utilada_2.9.0_bd635f55\ac10fb78a1ec09a130a5fb609bab22532a32ca83a6407ca1b1a4eb802dd3a31f\src\base\log\util-log-appenders-rolling_files.adb|
| Please submit a bug report at the SPARK issue tracker: |
| https://github.com/AdaCore/spark2014 . |
| Use a subject line meaningful to you and us to track the bug. |
| Include the entire contents of this bug box in the report. |
| Include the exact command that you entered. |
| Also include sources listed below. |
+==========================================================================+

Please include these source files with error report
Note that list may not be accurate in some cases,
so please double check that the problem can still
be reproduced with the set of files listed.
Consider also -gnatd.n switch (see debug.adb).

C:\Users\DAVYO\AppData\Local\alire\cache\builds\utilada_2.9.0_bd635f55\ac10fb78a1ec09a130a5fb609bab22532a32ca83a6407ca1b1a4eb802dd3a31f\src\base\log\util-log-appenders-rolling_files.adb
C:\Users\DAVYO\AppData\Local\alire\cache\builds\utilada_2.9.0_bd635f55\ac10fb78a1ec09a130a5fb609bab22532a32ca83a6407ca1b1a4eb802dd3a31f\src\base\log\util-log-appenders-rolling_files.ads
C:\Users\DAVYO\AppData\Local\alire\cache\builds\utilada_2.9.0_bd635f55\ac10fb78a1ec09a130a5fb609bab22532a32ca83a6407ca1b1a4eb802dd3a31f\src\base\log\util-log-appenders.ads
C:\Users\DAVYO\AppData\Local\alire\cache\builds\utilada_2.9.0_bd635f55\ac10fb78a1ec09a130a5fb609bab22532a32ca83a6407ca1b1a4eb802dd3a31f\src\base\log\util-log.ads
C:\Users\DAVYO\AppData\Local\alire\cache\builds\utilada_2.9.0_bd635f55\ac10fb78a1ec09a130a5fb609bab22532a32ca83a6407ca1b1a4eb802dd3a31f\src\core\util.ads
C:\Users\DAVYO\AppData\Local\alire\cache\builds\utilada_2.9.0_bd635f55\ac10fb78a1ec09a130a5fb609bab22532a32ca83a6407ca1b1a4eb802dd3a31f\src\base\properties\util-properties.ads
C:\Users\DAVYO\AppData\Local\alire\cache\builds\utilada_2.9.0_bd635f55\ac10fb78a1ec09a130a5fb609bab22532a32ca83a6407ca1b1a4eb802dd3a31f\src\base\beans\util-beans.ads
C:\Users\DAVYO\AppData\Local\alire\cache\builds\utilada_2.9.0_bd635f55\ac10fb78a1ec09a130a5fb609bab22532a32ca83a6407ca1b1a4eb802dd3a31f\src\base\beans\util-beans-objects.ads
C:\Users\DAVYO\AppData\Local\alire\cache\builds\utilada_2.9.0_bd635f55\ac10fb78a1ec09a130a5fb609bab22532a32ca83a6407ca1b1a4eb802dd3a31f\src\core\util-blobs.ads
C:\Users\DAVYO\AppData\Local\alire\cache\builds\utilada_2.9.0_bd635f55\ac10fb78a1ec09a130a5fb609bab22532a32ca83a6407ca1b1a4eb802dd3a31f\src\core\util-refs.ads
C:\Users\DAVYO\AppData\Local\alire\cache\builds\utilada_2.9.0_bd635f55\ac10fb78a1ec09a130a5fb609bab22532a32ca83a6407ca1b1a4eb802dd3a31f\src\core\concurrent\util-concurrent.ads
C:\Users\DAVYO\AppData\Local\alire\cache\builds\utilada_2.9.0_bd635f55\ac10fb78a1ec09a130a5fb609bab22532a32ca83a6407ca1b1a4eb802dd3a31f\src\core\concurrent\asm-intrinsic\util-concurrent-counters.ads
C:\Users\DAVYO\AppData\Local\alire\cache\builds\utilada_2.9.0_bd635f55\ac10fb78a1ec09a130a5fb609bab22532a32ca83a6407ca1b1a4eb802dd3a31f\src\base\beans\util-beans-basic.ads
C:\Users\DAVYO\AppData\Local\alire\cache\builds\utilada_2.9.0_bd635f55\ac10fb78a1ec09a130a5fb609bab22532a32ca83a6407ca1b1a4eb802dd3a31f\src\core\strings\util-strings.ads
C:\Users\DAVYO\AppData\Local\alire\cache\builds\utilada_2.9.0_bd635f55\ac10fb78a1ec09a130a5fb609bab22532a32ca83a6407ca1b1a4eb802dd3a31f\src\core\strings\util-strings-vectors.ads
C:\Users\DAVYO\AppData\Local\alire\cache\builds\utilada_2.9.0_bd635f55\ac10fb78a1ec09a130a5fb609bab22532a32ca83a6407ca1b1a4eb802dd3a31f\src\core\strings\util-strings-builders.ads
C:\Users\DAVYO\AppData\Local\alire\cache\builds\utilada_2.9.0_bd635f55\ac10fb78a1ec09a130a5fb609bab22532a32ca83a6407ca1b1a4eb802dd3a31f\src\core\texts\util-texts.ads
C:\Users\DAVYO\AppData\Local\alire\cache\builds\utilada_2.9.0_bd635f55\ac10fb78a1ec09a130a5fb609bab22532a32ca83a6407ca1b1a4eb802dd3a31f\src\core\texts\util-texts-builders.ads
C:\Users\DAVYO\AppData\Local\alire\cache\builds\utilada_2.9.0_bd635f55\ac10fb78a1ec09a130a5fb609bab22532a32ca83a6407ca1b1a4eb802dd3a31f\src\core\util-named_lists.ads
C:\Users\DAVYO\AppData\Local\alire\cache\builds\utilada_2.9.0_bd635f55\ac10fb78a1ec09a130a5fb609bab22532a32ca83a6407ca1b1a4eb802dd3a31f\src\base\log\util-log-formatters.ads
C:\Users\DAVYO\AppData\Local\alire\cache\builds\utilada_2.9.0_bd635f55\ac10fb78a1ec09a130a5fb609bab22532a32ca83a6407ca1b1a4eb802dd3a31f\src\core\strings\util-strings-formats.ads
C:\Users\DAVYO\AppData\Local\alire\cache\builds\utilada_2.9.0_bd635f55\ac10fb78a1ec09a130a5fb609bab22532a32ca83a6407ca1b1a4eb802dd3a31f\src\base\files\util-files.ads
C:\Users\DAVYO\AppData\Local\alire\cache\builds\utilada_2.9.0_bd635f55\ac10fb78a1ec09a130a5fb609bab22532a32ca83a6407ca1b1a4eb802dd3a31f\src\core\strings\util-strings-maps.ads
C:\Users\DAVYO\AppData\Local\alire\cache\builds\utilada_2.9.0_bd635f55\ac10fb78a1ec09a130a5fb609bab22532a32ca83a6407ca1b1a4eb802dd3a31f\src\base\files\util-files-rolling.ads
C:\Users\DAVYO\AppData\Local\alire\cache\builds\utilada_2.9.0_bd635f55\ac10fb78a1ec09a130a5fb609bab22532a32ca83a6407ca1b1a4eb802dd3a31f\src\base\properties\util-properties-basic.ads
C:\Users\DAVYO\AppData\Local\alire\cache\builds\utilada_2.9.0_bd635f55\ac10fb78a1ec09a130a5fb609bab22532a32ca83a6407ca1b1a4eb802dd3a31f\src\base\properties\util-properties-discrete.ads
C:\Users\DAVYO\AppData\Local\alire\cache\builds\utilada_2.9.0_bd635f55\ac10fb78a1ec09a130a5fb609bab22532a32ca83a6407ca1b1a4eb802dd3a31f\src\base\log\util-log-appenders-formatter.ads
C:\Users\DAVYO\AppData\Local\alire\cache\builds\utilada_2.9.0_bd635f55\ac10fb78a1ec09a130a5fb609bab22532a32ca83a6407ca1b1a4eb802dd3a31f\src\base\log\util-log-appenders-formatter.adb
C:\Users\DAVYO\AppData\Local\alire\cache\builds\utilada_2.9.0_bd635f55\ac10fb78a1ec09a130a5fb609bab22532a32ca83a6407ca1b1a4eb802dd3a31f\src\base\files\util-files-rolling.adb
C:\Users\DAVYO\AppData\Local\alire\cache\builds\utilada_2.9.0_bd635f55\ac10fb78a1ec09a130a5fb609bab22532a32ca83a6407ca1b1a4eb802dd3a31f\src\base\dates\util-dates.ads
C:\Users\DAVYO\AppData\Local\alire\cache\builds\utilada_2.9.0_bd635f55\ac10fb78a1ec09a130a5fb609bab22532a32ca83a6407ca1b1a4eb802dd3a31f\src\base\dates\util-dates-simple_format.ads
C:\Users\DAVYO\AppData\Local\alire\cache\builds\utilada_2.9.0_bd635f55\ac10fb78a1ec09a130a5fb609bab22532a32ca83a6407ca1b1a4eb802dd3a31f\src\core\texts\util-texts-builders.adb

compilation abandoned
gnatprove: error during generation of Global contracts
ERROR: Command ["gnatprove", "-P", "investments.gpr"] exited with code 1
PS W:\01-odavy\devel\ada\investments>

Start by reproducing gnatprove -P investments.gpr from the report and inspect the failure at util-log-appenders-rolling_files.ads:75 in util-log-appenders-rolling_files.adb. Review the listed rolling-file and logging sources, then determine whether the reported internal error can be isolated to this input. Done means the failure is reproduced with a clear diagnosis or no longer occurs for the supplied project.