Euro-Office · Phenitix · Aug 23, 2026 · Aug 23, 2026 · Aug 23, 2026 · Aug 23, 2026
@@ -21,13 +21,31 @@
 )
 
 modules_needed = [ "headers", "system", "filesystem", "regex", "date_time" ]
-header_only_modules_needed = [ "any", "asio", "beast", "foreach", "format", "functional", "multi_index", "uuid" ]
+# Only these submodules get checked out, so every boost header the project
+# includes must be reachable from this list (directly or as a boostdep-resolved
+# dependency of one of them).
+#
+# ptr_container / serialization / spirit / variant are listed explicitly because
+# they are NOT dependencies of anything above: they used to be pulled in
+# transitively on 1.78, but boost has been migrating away from Boost.Variant
+# towards std::variant, so on current boost they are no longer dragged in and
+# the headers went missing -> "fatal error C1083: Cannot open include file:
+# 'boost/variant.hpp'" in libetonyek, and the same for the spirit / ptr_container
+# / boost-archive includes in librevenge.
+#
+# NOTE: boost/archive/** (the base64 iterators librevenge uses) ships in the
+# SERIALIZATION module - there is no boost module called "archive". Those
+# iterators are pure templates, so headers alone are enough and serialization
+# does not have to be built.
+header_only_modules_needed = [ "any", "asio", "beast", "foreach", "format", "functional",
+                               "multi_index", "ptr_container", "serialization", "spirit",
+                               "uuid", "variant" ]
 
 def fetch_and_patch():
     nc.create_workdir()
     print( "Clone Boost 1.78.0..." )
     nc.run_command(
-        [ "git", "clone", "https://github.com/boostorg/boost.git", "-b", "boost-1.78.0", nc.work_dir, "--depth", "1" ],
+        [ "git", "clone", "https://github.com/boostorg/boost.git", nc.work_dir, "--depth", "1" ],
         "Clone Boost 1.78.0"
     )
 
@@ -70,6 +88,36 @@ def boost_msvc_arch() -> tuple[ str, str ]:
         return "arm", "Hostarm64\\arm64"
     nc.abort_op( f"Unsupported target arch for boost: {a!r}" )
 
+def jam_path( p ) -> str:
+    return str( Path( p ) ).replace( "\\", "\\\\" )
+
+def boost_msvc_toolset_version() -> str:
+    """
+    The 'using msvc : <version>' value for the compiler we actually build with.
+
+    Boost derives the library name tag from this value - common.jam's
+    toolset-tag joins major+minor, so 14.0 -> vc140, 14.3 -> vc143,
+    14.5 -> vc145. CMake's BoostConfig computes the same tag from the compiler
+    it detects and REJECTS libs whose tag differs:
+
+        libboost_filesystem-vc140-mt-x64-1_92.lib (vc140, detected vc145)
+        No suitable build variant has been found.
+
+    which is exactly what happened while this was hardcoded to 14.0 but cl.exe
+    came from MSVC 14.51 - the libs were built by the right compiler, only the
+    name lied. So derive it from the toolchain actually in use.
+
+    MSVC's tag keeps only the FIRST digit of the minor version (14.51 -> vc145,
+    14.39 -> vc143), hence 'MAJOR.<first digit of MINOR>' from VCToolsVersion.
+    """
+    ver = os.environ.get( "VCToolsVersion", "" )
+    parts = ver.split( "." )
+    if len( parts ) < 2 or not parts[ 0 ].isdigit() or not parts[ 1 ][ :1 ].isdigit():
+        nc.abort_op(
+            f"Cannot derive the MSVC toolset version from VCToolsVersion={ ver!r }. "
+            "Is the MSVC environment loaded (vcvars)?"
+        )
+    return f"{ parts[ 0 ] }.{ parts[ 1 ][ 0 ] }"
 
 def build_and_install():
     nc.create_install_dir()
@@ -94,14 +142,27 @@ def build_and_install():
 
     if nc.is_windows():
         print( "Fixing project-config.jam..." )
+        msvc_version = boost_msvc_toolset_version()
+        print( f"Using MSVC toolset { msvc_version } "
+               f"(libs will be tagged vc{ msvc_version.replace( '.', '' ) })" )
+        # Jam treats a backslash inside a quoted string as an escape, so a raw
+        # Windows path silently collapses ("C:\Program Files\..." arrives as
+        # "C:Program Files...") and b2 then warns "Did not find command for MSVC
+        # toolset" and falls back to whatever cl.exe is on PATH. jam_path()
+        # doubles the separators, which is exactly what it exists for.
+        # Built outside the f-string so no backslash appears in an f-string
+        # expression (only allowed from Python 3.12 on).
+        cl_path = jam_path(
+            Path( os.environ[ "VCToolsInstallDir" ] ) / "bin" / host_subdir / "cl.exe"
+        )
         content = f"""
 # Boost.Build Configuration
 # Generated by nc-build.py
- 
+
 import option ;
- 
-using msvc : 14.0 : "{ os.environ[ "VCToolsInstallDir" ] }\\bin\\{ host_subdir }\\cl.exe";
- 
+
+using msvc : { msvc_version } : "{ cl_path }";
+
 option.set keep-going : false ;
 
 """

@@ -3056,7 +3056,13 @@ Integer::Integer(const byte *encodedInteger, size_t byteCount, Signedness s, Byt
 	else
 	{
 		SecByteBlock block(byteCount);
-#if (_MSC_VER >= 1500)
+// The stdext:: iterator extensions were removed from the MSVC STL (gone as of
+// MSVC 14.51 / _MSC_VER 1951), so a pure version check picks a namespace that
+// no longer exists: "error C2653: 'stdext': is not a class or namespace".
+// Gate on _STDEXT_BEGIN - the macro the MSVC headers use to open that namespace -
+// like the guard in zdeflate.cpp already does. The portable path below is
+// equivalent; the wrapper only added debug-time bounds checking.
+#if (_MSC_VER >= 1500) && defined(_STDEXT_BEGIN)
 		std::reverse_copy(encodedInteger, encodedInteger+byteCount,
 			stdext::make_checked_array_iterator(block.begin(), block.size()));
 #else

@@ -418,7 +418,11 @@ unsigned int Deflator::LongestMatch(unsigned int &bestMatch) const
 #else
 				std::mismatch
 #endif
-#if _MSC_VER >= 1600
+// Same _STDEXT_BEGIN feature test as the guard above: the stdext:: extensions
+// are gone from the MSVC STL (as of MSVC 14.51 / _MSC_VER 1951), so a bare
+// version check would name a namespace that no longer exists. The unchecked
+// wrappers only suppressed iterator-debug warnings, so raw pointers are equivalent.
+#if _MSC_VER >= 1600 && defined(_STDEXT_BEGIN)
 				(stdext::make_unchecked_array_iterator(scan)+3, stdext::make_unchecked_array_iterator(scanEnd), stdext::make_unchecked_array_iterator(match)+3).first - stdext::make_unchecked_array_iterator(scan));
 #else
 				(scan+3, scanEnd, match+3).first - scan);

@@ -8,7 +8,43 @@ if [[ $install_dir == /mnt/* ]]; then
 fi
 
 export PATH="$PATH:/usr/bin"
-export PYTHON=/usr/bin/python3
+
+# Pick a working Python 3 for ICU's data/rules.mk generation. Prefer Cygwin's
+# python3, but fall back to any python3/python on PATH (e.g. the native Windows
+# one the build front-loads) when Cygwin's isn't installed. ICU's databuilder
+# normalizes path separators to '/', so native Python produces correct makefile
+# fragments too.
+if [ -x /usr/bin/python3 ]; then
+    export PYTHON=/usr/bin/python3
+elif command -v python3 >/dev/null 2>&1; then
+    export PYTHON="$( command -v python3 )"
+elif command -v python >/dev/null 2>&1; then
+    export PYTHON="$( command -v python )"
+else
+    echo "ERROR: no Python 3 found. Install Cygwin's python3, or ensure a native python3 is on PATH." >&2
+    exit 1
+fi
+echo "Using PYTHON=$PYTHON"
+
+# --- Make MSVC's link.exe win over Cygwin's /usr/bin/link (coreutils) --------
+# ICU's configure runs `link --version` and aborts with "link.exe is not a
+# valid linker" if it reports "GNU coreutils". Cygwin ships such a `link`, and
+# depending on the inherited PATH order it can shadow MSVC's linker. cl is
+# already on PATH (CC=cl) and MSVC's link.exe lives in the SAME directory, so
+# front-load that directory; falls back to VCToolsInstallDir if cl isn't found.
+msvc_bin=""
+cl_path="$( command -v cl 2>/dev/null || true )"
+if [ -n "$cl_path" ]; then
+    msvc_bin="$( dirname "$cl_path" )"
+elif [ -n "$VCToolsInstallDir" ]; then
+    msvc_bin="$( cygpath -u "$VCToolsInstallDir" )/bin/Hostx64/x64"
+fi
+if [ -n "$msvc_bin" ] && [ -x "$msvc_bin/link.exe" ]; then
+    export PATH="$msvc_bin:$PATH"
+    echo "Front-loaded MSVC bin so link.exe resolves to the MS linker: $msvc_bin"
+else
+    echo "WARNING: could not locate MSVC bin dir; Cygwin's link may shadow link.exe" >&2
+fi
 
 abort_op()
 {

@@ -40,8 +40,22 @@ echo Using Cygwin: %CYGWIN_BIN%
 echo Using vcvars: %VCVARS%
 
 REM ---- PATH ORDER: MSVC first, Cygwin second ----
-set "PATH=%CYGWIN_BIN%;%PATH%"
-call "%VCVARS%" || exit /b 1
+REM If the caller already loaded the MSVC environment (build.ps1 does this via
+REM Import-VcVars, so VCINSTALLDIR/VSCMD/PATH/INCLUDE/LIB are inherited here),
+REM DON'T re-run vcvars: it concatenates all MSVC/SDK dirs onto the already-long
+REM inherited PATH again and blows past cmd's 8191-char line limit
+REM ("Die eingegebene Zeile ist zu lang. / Syntaxfehler."), aborting the build.
+if defined VCINSTALLDIR (
+  echo MSVC environment already active ^(VCINSTALLDIR set^) - reusing it, skipping vcvars.
+  REM Cygwin is already on the inherited PATH; append (not prepend) so MSVC's
+  REM link.exe still precedes Cygwin's /usr/bin/link. Keeps cygpath reachable
+  REM even when the batch is run standalone from a VS dev prompt.
+  set "PATH=%PATH%;%CYGWIN_BIN%"
+) else (
+  REM Fresh shell: Cygwin first, then let vcvars prepend MSVC on top -> MSVC first.
+  set "PATH=%CYGWIN_BIN%;%PATH%"
+  call "%VCVARS%" || exit /b 1
+)
 
 echo "------------- DBG 1"
 

@@ -6,7 +6,43 @@ if [[ $install_dir == /mnt/* ]]; then
 fi
 
 export PATH="$PATH:/usr/bin"
-export PYTHON=/usr/bin/python3
+
+# Pick a working Python 3 for ICU's data/rules.mk generation. Prefer Cygwin's
+# python3, but fall back to any python3/python on PATH (e.g. the native Windows
+# one the build front-loads) when Cygwin's isn't installed. ICU's databuilder
+# normalizes path separators to '/', so native Python produces correct makefile
+# fragments too.
+if [ -x /usr/bin/python3 ]; then
+    export PYTHON=/usr/bin/python3
+elif command -v python3 >/dev/null 2>&1; then
+    export PYTHON="$( command -v python3 )"
+elif command -v python >/dev/null 2>&1; then
+    export PYTHON="$( command -v python )"
+else
+    echo "ERROR: no Python 3 found. Install Cygwin's python3, or ensure a native python3 is on PATH." >&2
+    exit 1
+fi
+echo "Using PYTHON=$PYTHON"
+
+# --- Make MSVC's link.exe win over Cygwin's /usr/bin/link (coreutils) --------
+# ICU's configure runs `link --version` and aborts with "link.exe is not a
+# valid linker" if it reports "GNU coreutils". Cygwin ships such a `link`, and
+# depending on the inherited PATH order it can shadow MSVC's linker. cl is
+# already on PATH (CC=cl) and MSVC's link.exe lives in the SAME directory, so
+# front-load that directory; falls back to VCToolsInstallDir if cl isn't found.
+msvc_bin=""
+cl_path="$( command -v cl 2>/dev/null || true )"
+if [ -n "$cl_path" ]; then
+    msvc_bin="$( dirname "$cl_path" )"
+elif [ -n "$VCToolsInstallDir" ]; then
+    msvc_bin="$( cygpath -u "$VCToolsInstallDir" )/bin/Hostx64/x64"
+fi
+if [ -n "$msvc_bin" ] && [ -x "$msvc_bin/link.exe" ]; then
+    export PATH="$msvc_bin:$PATH"
+    echo "Front-loaded MSVC bin so link.exe resolves to the MS linker: $msvc_bin"
+else
+    echo "WARNING: could not locate MSVC bin dir; Cygwin's link may shadow link.exe" >&2
+fi
 
 # --- logging: write a clean UTF-8 log straight from bash ---------------------
 # Done before any heavy work so the real output never passes through the

@@ -52,8 +52,22 @@ echo Using Cygwin: %CYGWIN_BIN%
 echo Using vcvars: %VCVARS%
 
 REM ---- PATH ORDER: MSVC first, Cygwin second ----
-set "PATH=%CYGWIN_BIN%;%PATH%"
-call "%VCVARS%" || exit /b 1
+REM If the caller already loaded the MSVC environment (build.ps1 does this via
+REM Import-VcVars, so VCINSTALLDIR/VSCMD/PATH/INCLUDE/LIB are inherited here),
+REM DON'T re-run vcvars: it concatenates all MSVC/SDK dirs onto the already-long
+REM inherited PATH again and blows past cmd's 8191-char line limit
+REM ("Die eingegebene Zeile ist zu lang. / Syntaxfehler."), aborting the build.
+if defined VCINSTALLDIR (
+  echo MSVC environment already active ^(VCINSTALLDIR set^) - reusing it, skipping vcvars.
+  REM Cygwin is already on the inherited PATH; append (not prepend) so MSVC's
+  REM link.exe still precedes Cygwin's /usr/bin/link. Keeps cygpath reachable
+  REM even when the batch is run standalone from a VS dev prompt.
+  set "PATH=%PATH%;%CYGWIN_BIN%"
+) else (
+  REM Fresh shell: Cygwin first, then let vcvars prepend MSVC on top -> MSVC first.
+  set "PATH=%CYGWIN_BIN%;%PATH%"
+  call "%VCVARS%" || exit /b 1
+)
 
 echo "------------- DBG 1"
 

@@ -27,6 +27,28 @@
 
 gn_source_path = nc.work_dir / "gn-source"
 
+# Enable git long paths for EVERY git process started from here on - including
+# the ones gclient spawns internally, which we can't pass -c flags to.
+# GIT_CONFIG_COUNT/KEY/VALUE (git >= 2.31) outranks the system/global config, so
+# this works without touching the user's ~/.gitconfig (which may not even exist -
+# depot_tools then warns about it, harmlessly).
+#
+# Why it's needed: some v8 dependency paths exceed MAX_PATH, e.g.
+# buildtools/third_party/libc++/trunk/test/std/thread/... = 264 chars. Without
+# this git cannot write those files, reports "Filename too long", and the
+# unwritten file shows up as a local deletion -> gclient aborts the sync with
+# "You have uncommitted changes". The Windows-wide LongPathsEnabled registry
+# flag does NOT cover this; git needs its own opt-in.
+#
+# Deliberately ONLY longpaths. depot_tools also recommends core.autocrlf=false,
+# but do NOT set it here: an existing tree checked out with CRLF no longer
+# matches the LF patches in tools/8.9/, and every `git apply` fails with
+# "patch does not apply".
+if nc.is_windows():
+    os.environ[ "GIT_CONFIG_COUNT" ] = "1"
+    os.environ[ "GIT_CONFIG_KEY_0" ] = "core.longpaths"
+    os.environ[ "GIT_CONFIG_VALUE_0" ] = "true"
+
 def check_prequisites():
     tools_needed = [ "git", "python3" ]
     if nc.is_linux():

@@ -199,6 +199,17 @@ else()
     set(Boost_USE_STATIC_LIBS ON)
     find_package( Boost REQUIRED COMPONENTS system filesystem regex date_time )
 
+    # Boost.Regex is header-only since Boost 1.77, so Boost::regex is now an
+    # INTERFACE target. For the COMPILED components (filesystem, ...) Boost's own
+    # CMake config sets BOOST_<LIB>_NO_LIB, which switches off the auto-link
+    # #pragma in the headers because CMake passes the .lib path itself. A
+    # header-only target gets no such define AND no library directory, yet
+    # boost/regex/v5/cregex.hpp still emits the auto-link pragma - so the linker
+    # demands libboost_regex-vcXXX-mt-x64-Y_ZZ.lib and fails with LNK1104 even
+    # though nothing needs to be linked. On Boost 1.78 regex was still a compiled
+    # component, hence the define came for free and this never surfaced.
+    add_definitions(-DBOOST_REGEX_NO_LIB)
+
     # Setup v8
     set(V8_INSTALL_DIR "${EO_CORE_3RD_PARTY_INSTALL_DIR}/v8")
     get_filename_component(V8_INSTALL_DIR_ABS "${V8_INSTALL_DIR}" ABSOLUTE)