diff --git a/CMake/PickyWarnings.cmake b/CMake/PickyWarnings.cmake
index 400e0be77a..a711efaea7 100644
--- a/CMake/PickyWarnings.cmake
+++ b/CMake/PickyWarnings.cmake
@@ -206,7 +206,7 @@ if(PICKY_COMPILER)
         list(APPEND WPICKY_ENABLE
           -Walloc-zero                     #             gcc  7.0
           -Wduplicated-branches            #             gcc  7.0
-          -Wformat-overflow=2              #             gcc  7.0
+          -Wno-format-overflow             #             gcc  7.0
           -Wformat-truncation=2            #             gcc  7.0
           -Wimplicit-fallthrough           # clang  4.0  gcc  7.0
           -Wrestrict                       #             gcc  7.0
diff --git a/m4/curl-compilers.m4 b/m4/curl-compilers.m4
index 27b84f861a..0fde2f9455 100644
--- a/m4/curl-compilers.m4
+++ b/m4/curl-compilers.m4
@@ -1068,7 +1068,7 @@ AC_DEFUN([CURL_SET_COMPILER_WARNING_OPTS], [
             CURL_ADD_COMPILER_WARNINGS([tmp_CFLAGS], [duplicated-branches])
             CURL_ADD_COMPILER_WARNINGS([tmp_CFLAGS], [restrict])
             CURL_ADD_COMPILER_WARNINGS([tmp_CFLAGS], [alloc-zero])
-            tmp_CFLAGS="$tmp_CFLAGS -Wformat-overflow=2"
+            tmp_CFLAGS="$tmp_CFLAGS -Wno-format-overflow"
             tmp_CFLAGS="$tmp_CFLAGS -Wformat-truncation=2"
             tmp_CFLAGS="$tmp_CFLAGS -Wimplicit-fallthrough"
           fi