The bundled minizip in xlswriter has K&R C function declarations in
multiple files (mztools.c, ioapi.c). Apple Clang (Xcode 16+) defaults
to C23, which removed K&R from the standard, causing hard build errors.
Instead of patching individual files, downgrade the C standard to gnu17
for the whole build when xlswriter is enabled. This covers all K&R
occurrences in the bundled code.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
The bundled minizip in xlswriter (pinned at libxlsxwriter RELEASE_1.0.0)
uses a K&R-style function declaration in mztools.c. Modern Clang on macOS
(defaulting to C23) rejects this as a hard syntax error since K&R
declarations were removed from the C23 standard.
The upstream libxlsxwriter has already fixed this on their main branch.
This patch applies the same fix during the build process.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Both libraries are listed in lib.json and used as transitive dependencies
(libaom via libavif, brotli via freetype/curl) but had no Windows builder,
causing builds to fail with "library [X] is in the lib.json list but not
supported to compile".
libaom: Uses builddir instead of build to avoid collision with the
source tree's build/cmake/ directory. Matches the Unix builder's
AOM_TARGET_CPU=generic setting for portability.
brotli: Standard CMake build with shared libs and tools disabled.
Also adds static-libs-windows entry for libaom in lib.json.
