diff --git a/CMake/PickyWarnings.cmake b/CMake/PickyWarnings.cmake
index b7bb20efe2..b0ec49ac9f 100644
--- a/CMake/PickyWarnings.cmake
+++ b/CMake/PickyWarnings.cmake
@@ -268,6 +268,9 @@ if(PICKY_COMPILER)
       if(NOT CMAKE_C_COMPILER_VERSION VERSION_LESS 4.3 AND CMAKE_C_COMPILER_VERSION VERSION_LESS 4.8)
         list(APPEND _picky "-Wno-type-limits")  # Avoid false positives
       endif()
+      if(NOT CMAKE_C_COMPILER_VERSION VERSION_LESS 5.1 AND CMAKE_C_COMPILER_VERSION VERSION_LESS 5.5)
+        list(APPEND _picky "-Wno-conversion")  # Avoid false positives
+      endif()
     endif()
   endif()
 endif()
diff --git a/m4/curl-compilers.m4 b/m4/curl-compilers.m4
index cbf7dc8a3b..6456c3e576 100644
--- a/m4/curl-compilers.m4
+++ b/m4/curl-compilers.m4
@@ -1131,6 +1131,10 @@ AC_DEFUN([CURL_SET_COMPILER_WARNING_OPTS], [
           dnl Avoid false positives
           tmp_CFLAGS="$tmp_CFLAGS -Wno-type-limits"
         fi
+        if test "$compiler_num" -ge "501" -a "$compiler_num" -lt "505"; then
+          dnl Avoid false positives
+          tmp_CFLAGS="$tmp_CFLAGS -Wno-conversion"
+        fi
         ;;
         #
       HP_UX_C)