--- cmake-3.30.1/Modules/CMakeDetermineSystem.cmake.orig
+++ cmake-3.30.1/Modules/CMakeDetermineSystem.cmake
@@ -101,6 +101,12 @@
         RESULT_VARIABLE val
         OUTPUT_STRIP_TRAILING_WHITESPACE
         ERROR_QUIET)
+    elseif(CMAKE_HOST_SYSTEM_NAME STREQUAL "SunOS")
+      execute_process(COMMAND isainfo -n
+        OUTPUT_VARIABLE CMAKE_HOST_SYSTEM_PROCESSOR
+        RESULT_VARIABLE val
+        OUTPUT_STRIP_TRAILING_WHITESPACE
+        ERROR_QUIET)
     else()
       execute_process(COMMAND ${CMAKE_UNAME} -p
         OUTPUT_VARIABLE CMAKE_HOST_SYSTEM_PROCESSOR