Add option to enable legacy macros.

CMakeLists.txt

@@ -547,6 +547,11 @@ else()
   set(NETCDF_ENABLE_HDF4 OFF)
 endif()
 
+# Option legacy  macros 
+# Do we want to enable unsafe macros, e.g. _FillValue in addition to NC_FillValue.
+# See https://github.com/Unidata/netcdf-c/issues/3029
+option(NETCDF_ENABLE_LEGACY_MACROS "Enable legacy macros for backwards compatibility. Use with Caution." OFF)
+
 # Option Logging, only valid for netcdf4 dispatchers.
 option(NETCDF_ENABLE_LOGGING "Enable Logging." OFF)
 if(NOT NETCDF_ENABLE_NETCDF4)

config.h.cmake.in

@@ -496,6 +496,9 @@ with zip */
 /* Idspatch table version */
 #cmakedefine NC_DISPATCH_VERSION ${NC_DISPATCH_VERSION}
 
+/* Enable Legacy, potential-conflict Macro _FillValue */
+#cmakedefine NETCDF_ENABLE_LEGACY_MACROS
+
 /* no IEEE float on this platform */
 #cmakedefine NO_IEEE_FLOAT 1
 

configure.ac

@@ -464,13 +464,13 @@ fi
 
 # Do we want to enable unsafe macros, e.g. _FillValue in addition to NC_FillValue.
 # See https://github.com/Unidata/netcdf-c/issues/3029
-AC_MSG_CHECKING([whether to allow unsafe macros])
-AC_ARG_ENABLE([unsafe-macros],
-               [AS_HELP_STRING([--enable-unsafe-macros],
-                              [enable unsafe macros for backwards compatibility purposes. Use with caution.\
+AC_MSG_CHECKING([whether to allow legacy macros])
+AC_ARG_ENABLE([legacy-macros],
+               [AS_HELP_STRING([--enable-legacy-macros],
+                              [enable legacy macros for backwards compatibility purposes. Use with caution.\
                               This can lead to unexpected consequences/behavior.])])
-if test "x$enable_unsafe_macros" = xyes; then
-   AC_DEFINE([NETCDF_ENABLE_LEGACY_MACROS], 1, [If true, enable unsafe macros in netcdf.h])
+if test "x$enable_legacy_macros" = xyes; then
+   AC_DEFINE([NETCDF_ENABLE_LEGACY_MACROS], 1, [If true, enable legacy macros in netcdf.h])
 fi
 
 # Does the user want to allow reading of remote data via range headers?