diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 4be09ffe..cbab1a55 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -13,8 +13,8 @@ env:
   CTEST_OUTPUT_ON_FAILURE: "ON"
   DEBIAN_FRONTEND: noninteractive
   UPX_CMAKE_BUILD_FLAGS: --verbose
-  # 2023-11-01
-  ZIG_DIST_VERSION: 0.12.0-dev.1369+a09ba455c
+  # 2023-11-03
+  ZIG_DIST_VERSION: 0.12.0-dev.1390+94cee4fb2
 
 jobs:
   job-rebuild-and-verify-stubs:
@@ -146,8 +146,8 @@ jobs:
       fail-fast: false
       matrix:
         include:
-          # NOTE: macos does not have "env -C"; only with coreutils
-          # NOTE: macos-11 does not have "readlink -f"; only on macos >= 12 or with coreutils
+          # NOTE: macos does not have "env -C"; only with brew coreutils
+          # NOTE: macos-11 does not have "readlink -f"; only on macos >= 12 or with brew coreutils
           - { os: macos-11, gcc: gcc-10, gxx: 'g++-10', testsuite: true }
           - { os: macos-12, gcc: gcc-11, gxx: 'g++-11', testsuite: true }
           - { os: macos-13, gcc: gcc-12, gxx: 'g++-12', testsuite: true }
@@ -278,7 +278,7 @@ jobs:
           env -C build/release/Release upx_exe=./upx bash "$testsuite_1"
 
   job-windows-toolchains: # build "by hand" using cmd.exe
-    if: true
+    if: github.repository_owner == 'upx'
     needs: [ job-rebuild-and-verify-stubs ]
     name: ${{ format('windows {0}', matrix.name) }}
     runs-on: ${{ matrix.os }}
diff --git a/.github/workflows/weekly-ci-bs-by-hand.yml b/.github/workflows/weekly-ci-bs-by-hand.yml
index 854fd368..b698bcfd 100644
--- a/.github/workflows/weekly-ci-bs-by-hand.yml
+++ b/.github/workflows/weekly-ci-bs-by-hand.yml
@@ -104,6 +104,7 @@ jobs:
 
   job-by-hand-macos-clang: # uses a POSIX-compliant shell
     # ...and also uses a subdirectory "upx with space" in order to detect possible quoting issues
+    # ...and also uses ccache as we are running the same build-script again and again
     if: github.repository_owner == 'upx'
     strategy:
       fail-fast: false
@@ -168,7 +169,7 @@ jobs:
           export zlib_extra_flags="-DHAVE_VSNPRINTF"
           export AR=false # link without using $AR
           CC="clang $xflags" CXX="clang++ -std=gnu++17 $xflags" bash "./upx with space/misc/scripts/build_upx_by_hand.sh"
-          ls -l build/by-hand || true
+          ls -l "upx with space"/build/by-hand || true
       - name: 'Build by-hand with bash - gcc'
         if: success() || failure() # run this step even if the previous step failed
         shell: bash
@@ -176,3 +177,4 @@ jobs:
           xflags="-static -Wall -Wextra -Werror"
           # gcc uses the MingGW headers, so no extra settings are needed
           CC="gcc $xflags" CXX="g++ -std=gnu++17 $xflags" bash "./upx with space/misc/scripts/build_upx_by_hand.sh"
+          ls -l "upx with space"/build/by-hand || true
diff --git a/.github/workflows/weekly-ci-bs-misc.yml b/.github/workflows/weekly-ci-bs-misc.yml
index a141181f..feac7555 100644
--- a/.github/workflows/weekly-ci-bs-misc.yml
+++ b/.github/workflows/weekly-ci-bs-misc.yml
@@ -13,6 +13,7 @@ env:
 
 jobs:
   BS0:
+    if: github.repository_owner == 'upx'
     runs-on: ubuntu-latest
     container: 'alpine:edge'
     steps:
diff --git a/.github/workflows/weekly-ci-cc-alpine-linux.yml b/.github/workflows/weekly-ci-cc-alpine-linux.yml
index 77760ffc..230373df 100644
--- a/.github/workflows/weekly-ci-cc-alpine-linux.yml
+++ b/.github/workflows/weekly-ci-cc-alpine-linux.yml
@@ -38,8 +38,8 @@ jobs:
           - { container: 'alpine:3.16', use_cxx20: 1, use_cxx2b: 1, use_lto: 1 } # May 2022: C++2b; clang-13 & gcc-11
           - { container: 'alpine:3.17', use_cxx20: 1, use_cxx2b: 1, use_lto: 1 }
           - { container: 'alpine:3.18', use_cxx20: 1, use_cxx2b: 1, use_lto: 1 }
-          - { container: 'alpine:edge', use_cxx20: 1, use_cxx2b: 1, use_lto: 1 }
-          - { container: 'i386/alpine:edge', use_cxx20: 1, use_cxx2b: 1, use_lto: 1 }
+          - { container: 'alpine:edge', use_cxx20: 1, use_cxx23: 1, use_lto: 1 }
+          - { container: 'i386/alpine:edge', use_cxx20: 1, use_cxx23: 1, use_lto: 1 }
           # more 32-bit i386 versions, just for testing
           # { container: 'i386/alpine:3.9' }  # clang-5,  gcc-8; BROKEN: clang -m32 problem
           - { container: 'i386/alpine:3.10' } # clang-8,  gcc-8
@@ -185,6 +185,7 @@ jobs:
           for dir in "upx with space"/build/xtarget/*-cxx*/*; do
              echo "===== $dir"
              make -C "$dir" test
+             (cd "$dir" && ./upx --sysinfo -v)
           done
 
       - name: 'Run file system test suite (busybox)'
diff --git a/.github/workflows/weekly-ci-cc-llvm-mingw.yml b/.github/workflows/weekly-ci-cc-llvm-mingw.yml
index b7be9393..a3d21c33 100644
--- a/.github/workflows/weekly-ci-cc-llvm-mingw.yml
+++ b/.github/workflows/weekly-ci-cc-llvm-mingw.yml
@@ -55,16 +55,19 @@ jobs:
           CC="$CC -D_WIN32_WINNT=0x0400"; CXX="$CXX -D_WIN32_WINNT=0x0400"
           make UPX_XTARGET=aarch64-w64-mingw32-clang xtarget/debug xtarget/release
       - name: 'Build clang armv7'
+        if: success() || failure() # run this step even if the previous step failed
         run: |
           export CC="armv7-w64-mingw32-clang -static" CXX="armv7-w64-mingw32-clang++ -static"
           CC="$CC -D_WIN32_WINNT=0x0400"; CXX="$CXX -D_WIN32_WINNT=0x0400"
           make UPX_XTARGET=armv7-w64-mingw32-clang xtarget/debug xtarget/release
       - name: 'Build clang i686'
+        if: success() || failure() # run this step even if the previous step failed
         run: |
           export CC="i686-w64-mingw32-clang -static" CXX="i686-w64-mingw32-clang++ -static"
           CC="$CC -D_WIN32_WINNT=0x0400"; CXX="$CXX -D_WIN32_WINNT=0x0400"
           make UPX_XTARGET=i686-w64-mingw32-clang xtarget/debug xtarget/release
       - name: 'Build clang x86_64'
+        if: success() || failure() # run this step even if the previous step failed
         run: |
           export CC="x86_64-w64-mingw32-clang -static" CXX="x86_64-w64-mingw32-clang++ -static"
           CC="$CC -D_WIN32_WINNT=0x0400"; CXX="$CXX -D_WIN32_WINNT=0x0400"
diff --git a/.github/workflows/weekly-ci-cc-zigcc.yml b/.github/workflows/weekly-ci-cc-zigcc.yml
index b2b74806..1f420ab4 100644
--- a/.github/workflows/weekly-ci-cc-zigcc.yml
+++ b/.github/workflows/weekly-ci-cc-zigcc.yml
@@ -11,8 +11,8 @@ env:
   CMAKE_REQUIRED_QUIET: "OFF"
   CTEST_OUTPUT_ON_FAILURE: "ON"
   DEBIAN_FRONTEND: noninteractive
-  # 2023-11-01
-  ZIG_DIST_VERSION: 0.12.0-dev.1369+a09ba455c
+  # 2023-11-03
+  ZIG_DIST_VERSION: 0.12.0-dev.1390+94cee4fb2
 
 jobs:
   job-linux-zigcc: # uses cmake + make
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 001980cf..98e947e7 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -524,7 +524,7 @@ include(CTest)
 if(NOT CMAKE_CROSSCOMPILING)
     add_test(NAME upx-version COMMAND upx --version)
     add_test(NAME upx-help    COMMAND upx --help)
-    add_test(NAME upx-sysinfo COMMAND upx --sysinfo)
+    add_test(NAME upx-sysinfo COMMAND upx --sysinfo -v)
 endif()
 if(NOT CMAKE_CROSSCOMPILING AND NOT UPX_CONFIG_DISABLE_SELF_PACK_TEST)
     # IMPORTANT NOTE: these tests can only work if the host executable format is supported by UPX!
diff --git a/misc/scripts/upx-clang-format.sh b/misc/scripts/upx-clang-format.sh
index fe34d1c1..2d7a5a11 100755
--- a/misc/scripts/upx-clang-format.sh
+++ b/misc/scripts/upx-clang-format.sh
@@ -3,20 +3,21 @@
 set -e; set -o pipefail
 
 # "Gofmt's style is nobody's favourite, but gofmt is everybody's favourite." --Rob Pike
-
+#
 # NOTE: we are using clang-format-15.0.6 from upx-stubtools
 # see https://github.com/upx/upx-stubtools/releases
-
+#
 # NOTE: we use .clang-format config from upx.git/.clang-format
+# Copyright (C) Markus Franz Xaver Johannes Oberhumer
 
 if [[ ! -f $UPX_CLANG_FORMAT ]]; then
-UPX_CLANG_FORMAT="$HOME/local/bin/bin-upx/clang-format-15.0.6"
+    UPX_CLANG_FORMAT="$HOME/local/bin/bin-upx/clang-format-15.0.6"
 fi
 if [[ ! -f $UPX_CLANG_FORMAT ]]; then
-UPX_CLANG_FORMAT="$HOME/.local/bin/bin-upx/clang-format-15.0.6"
+    UPX_CLANG_FORMAT="$HOME/.local/bin/bin-upx/clang-format-15.0.6"
 fi
 if [[ ! -f $UPX_CLANG_FORMAT ]]; then
-UPX_CLANG_FORMAT="$HOME/bin/bin-upx/clang-format-15.0.6"
+    UPX_CLANG_FORMAT="$HOME/bin/bin-upx/clang-format-15.0.6"
 fi
 if [[ ! -f $UPX_CLANG_FORMAT ]]; then
     echo "ERROR: $0: cannot find clang-format-15.0.6"
@@ -29,4 +30,4 @@ ulimit -v 1048576 || true
 
 #echo $UPX_CLANG_FORMAT
 exec "$UPX_CLANG_FORMAT" -style=file "$@"
-exit 1
+exit 99
diff --git a/misc/testsuite/test_symlinks.sh b/misc/testsuite/test_symlinks.sh
index 9c41be70..9e15e963 100755
--- a/misc/testsuite/test_symlinks.sh
+++ b/misc/testsuite/test_symlinks.sh
@@ -3,16 +3,25 @@
 set -e; set -o pipefail
 argv0=$0; argv0abs=$(readlink -fn "$argv0"); argv0dir=$(dirname "$argv0abs")
 
+#
+# Copyright (C) Markus Franz Xaver Johannes Oberhumer
+#
+# test file system behaviour with symlinks; requires:
+#   $upx_exe                (required, but with convenience fallback "./upx")
+# optional settings:
+#   $upx_exe_runner         (e.g. "qemu-x86_64 -cpu Westmere" or "valgrind")
+#
+
+# IMPORTANT NOTE: do NOT run as user root!!
+# IMPORTANT NOTE: this script only works on Unix!!
+umask 0022
+
 # disable on macOS for now, see https://github.com/upx/upx/issues/612
 if [[ "$(uname)" == Darwin ]]; then
     echo "$0: SKIPPED"
     exit 0
 fi
 
-# IMPORTANT NOTE: do NOT run as user root!!
-# IMPORTANT NOTE: this script only works on Unix!!
-umask 0022
-
 id || true
 echo "PWD='$PWD'"
 if [[ $UID == 0 || $EUID == 0 ]]; then
@@ -20,11 +29,6 @@ if [[ $UID == 0 || $EUID == 0 ]]; then
     exit 91
 fi
 
-# test file system behaviour with symlinks; requires:
-#   $upx_exe                (required, but with convenience fallback "./upx")
-# optional settings:
-#   $upx_exe_runner         (e.g. "qemu-x86_64 -cpu Westmere" or "valgrind")
-
 #***********************************************************************
 # init & checks
 #***********************************************************************
diff --git a/misc/testsuite/upx_testsuite_1.sh b/misc/testsuite/upx_testsuite_1.sh
index 2e67e82e..693c41b4 100755
--- a/misc/testsuite/upx_testsuite_1.sh
+++ b/misc/testsuite/upx_testsuite_1.sh
@@ -3,6 +3,9 @@
 set -e; set -o pipefail
 argv0=$0; argv0abs=$(readlink -fn "$argv0"); argv0dir=$(dirname "$argv0abs")
 
+#
+# Copyright (C) Markus Franz Xaver Johannes Oberhumer
+#
 # very first version of the upx-testsuite; requires:
 #   $upx_exe                (required, but with convenience fallback "./upx")
 #   $upx_testsuite_SRCDIR   (required, but with convenience fallback)
@@ -14,6 +17,7 @@ argv0=$0; argv0abs=$(readlink -fn "$argv0"); argv0dir=$(dirname "$argv0abs")
 #   $UPX_TESTSUITE_LEVEL
 #
 # see https://github.com/upx/upx-testsuite.git
+#
 
 #***********************************************************************
 # init & checks
diff --git a/src/help.cpp b/src/help.cpp
index 981bb1ac..b847869d 100644
--- a/src/help.cpp
+++ b/src/help.cpp
@@ -467,6 +467,11 @@ void show_sysinfo(const char *options_var) {
             con_fprintf(f, fmt, v);
             con_fprintf(f, "\n");
         };
+        // language
+        cf_print("__cplusplus", "%lld", __cplusplus + 0, 3);
+#if defined(_MSVC_LANG)
+        cf_print("_MSVC_LANG", "%lld", _MSVC_LANG + 0, 3);
+#endif
         // compiler
 #if defined(ACC_CC_CLANG)
         cf_print("ACC_CC_CLANG", "0x%06llx", ACC_CC_CLANG + 0, 3);