Crash during config.

[grafikrobot]

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Environment and version details

• Operating System+version: Linux and Windows
• Compiler+version: Fil-C, mingw
• Shell: Bash
• B2 Version: 5.5.0, main
• B2 Configuration: Output of b2 --debug-configuration in your project.

notice: loading B2 from /home/runner/work/b2/b2/b2/src/build-system.jam
notice: Searching '/etc' '/home/runner' '/home/runner/work/b2/b2/b2/src/util' '/home/runner/work/b2/b2/b2/src/tools' '/home/runner/work/b2/b2/b2/src/options' '/home/runner/work/b2/b2/b2/src/engine' '/home/runner/work/b2/b2/b2/src/contrib' '/home/runner/work/b2/b2/b2/src/build' '/home/runner/work/b2/b2/b2/src' for site-config configuration file 'site-config.jam'.
notice: Configuration file 'site-config.jam' not found in '/etc' '/home/runner' '/home/runner/work/b2/b2/b2/src/util' '/home/runner/work/b2/b2/b2/src/tools' '/home/runner/work/b2/b2/b2/src/options' '/home/runner/work/b2/b2/b2/src/engine' '/home/runner/work/b2/b2/b2/src/contrib' '/home/runner/work/b2/b2/b2/src/build' '/home/runner/work/b2/b2/b2/src'.
notice: Searching '/home/runner' '/home/runner/work/b2/b2/b2/src/util' '/home/runner/work/b2/b2/b2/src/tools' '/home/runner/work/b2/b2/b2/src/options' '/home/runner/work/b2/b2/b2/src/engine' '/home/runner/work/b2/b2/b2/src/contrib' '/home/runner/work/b2/b2/b2/src/build' '/home/runner/work/b2/b2/b2/src' for user-config configuration file 'user-config.jam'.
notice: Loading user-config configuration file 'user-config.jam' from '/home/runner'.
notice: will use '/opt/fil/bin/fil++' for clang-linux, condition <toolset>clang-linux-20
warning: toolset clang-linux initialization: can not find tool windres
warning: initialized from /home/runner/user-config.jam:1
notice: using rc compiler :: <toolset>clang-linux-20 :: as

notice: loading B2 from D:/a/b2/b2/src/build-system.jam
notice: Searching 'C:\Users\runneradmin' 'D:\a\_temp\msys64\home\runneradmin' 'C:\Users\runneradmin' 'D:\a\b2\b2\src\build' 'D:\a\b2\b2\src\contrib' 'D:\a\b2\b2\src\engine' 'D:\a\b2\b2\src\options' 'D:\a\b2\b2\src\tools' 'D:\a\b2\b2\src\util' 'D:/a/b2/b2/src' for site-config configuration file 'site-config.jam'.
notice: Configuration file 'site-config.jam' not found in 'C:\Users\runneradmin' 'D:\a\_temp\msys64\home\runneradmin' 'C:\Users\runneradmin' 'D:\a\b2\b2\src\build' 'D:\a\b2\b2\src\contrib' 'D:\a\b2\b2\src\engine' 'D:\a\b2\b2\src\options' 'D:\a\b2\b2\src\tools' 'D:\a\b2\b2\src\util' 'D:/a/b2/b2/src'.
notice: Searching 'C:\Users\runneradmin' 'D:\a\_temp\msys64\home\runneradmin' 'C:\Users\runneradmin' 'D:\a\b2\b2\src\build' 'D:\a\b2\b2\src\contrib' 'D:\a\b2\b2\src\engine' 'D:\a\b2\b2\src\options' 'D:\a\b2\b2\src\tools' 'D:\a\b2\b2\src\util' 'D:/a/b2/b2/src' for user-config configuration file 'user-config.jam'.
notice: Configuration file 'user-config.jam' not found in 'C:\Users\runneradmin' 'D:\a\_temp\msys64\home\runneradmin' 'C:\Users\runneradmin' 'D:\a\b2\b2\src\build' 'D:\a\b2\b2\src\contrib' 'D:\a\b2\b2\src\engine' 'D:\a\b2\b2\src\options' 'D:\a\b2\b2\src\tools' 'D:\a\b2\b2\src\util' 'D:/a/b2/b2/src'.
notice: [cmdline-cfg] toolset clang not previously configured; attempting to auto-configure now
notice: will use 'clang++' for clang-linux, condition <toolset>clang-linux-21
notice: using rc compiler :: <toolset>clang-linux-21 :: windres

Brief problem description

Multiple environments crash when doing the initial config. Managed to get it during a Fil-C invocation which reports a violation. Otherwise it's non-deterministic.