Cmake build does not include svgz support

The cmake build scripts set HAVE_ZLIB when atttempting to build with_zlib. The existing autogen/configure build uses HAVE_LIBZ. Hence, the C #define is not enabled. The following changes fix this:

./ line 40:
#cmakedefine HAVE_LIBZ

./cmake/config_checks.cmake at line 37:
set(HAVE_LIBZ 1)

diff --git a/cmake/config_checks.cmake b/cmake/config_checks.cmake
index 57f9a19ad..6acaf7455 100644
--- a/cmake/config_checks.cmake
+++ b/cmake/config_checks.cmake
@@ -34,7 +34,7 @@ set( HAVE_LIBGD     ${GD_FOUND}         )
 set( HAVE_GS        ${GS_FOUND}         )
 set( HAVE_GTS       ${GTS_FOUND}        )
 if(with_zlib AND ZLIB_FOUND)
-  set(HAVE_ZLIB 1)
+  set(HAVE_LIBZ 1)
diff --git a/ b/
index 188a31e44..1e4e1ab57 100644
--- a/
+++ b/
@@ -37,7 +37,7 @@ typedef SSIZE_T ssize_t;
 #cmakedefine HAVE_GD_FONTCONFIG
 #cmakedefine HAVE_GD_FREETYPE
 #cmakedefine HAVE_GD_GIF
-#cmakedefine HAVE_ZLIB
+#cmakedefine HAVE_LIBZ
 #cmakedefine HAVE_GS
 #cmakedefine HAVE_GTS
 #cmakedefine HAVE_PANGOCAIRO

Thanks, well spotted. Do you want us to patch in your change or would you like to submit a merge request on gitlab?

Thank you for reaching out. If you wouldn’t mind applying it, I would be grateful.

I have a substantial rewrite of the MacOS code for the (updated for ARC, other Objective-C features since Snow Leopard, etc.), built on Sonoma with Xcode 15).

Aside from the source code changes, would there be other MacOS specific updates of value I could look into?
Thank you,
Keefe (zosmac)