diff --git a/cmake/pcre.cmake b/cmake/pcre.cmake
index b0c6b81e630..0ac834f44a6 100644
--- a/cmake/pcre.cmake
+++ b/cmake/pcre.cmake
@@ -43,6 +43,7 @@ MACRO(BUNDLE_PCRE2)
   ENDFOREACH()
   FOREACH(v "" "_DEBUG" "_RELWITHDEBINFO" "_RELEASE" "_MINSIZEREL")
     STRING(REPLACE "/WX" "" pcre2_flags${v} "${CMAKE_C_FLAGS${v}}")
+    SET(pcre2_flags${v} "${pcre2_flags${v}} -std=c99 ")
     IF(MSVC)
       # Suppress a warning
       STRING(APPEND pcre2_flags${v} " /wd4244 " )
@@ -53,8 +54,8 @@ MACRO(BUNDLE_PCRE2)
   ExternalProject_Add(
     pcre2
     PREFIX   "${dir}"
-    URL "https://github.com/PhilipHazel/pcre2/releases/download/pcre2-10.39/pcre2-10.39.zip"
-    URL_MD5  e101c0ca9edb4b0af103bebe78ba52b0
+    URL "https://github.com/PhilipHazel/pcre2/releases/download/pcre2-10.40/pcre2-10.40.zip"
+    URL_MD5 798698846982ce171d881ed0d7535c2a
     INSTALL_COMMAND ""
     CMAKE_ARGS
       "-DCMAKE_WARN_DEPRECATED=FALSE"