Hotfix packages with several fixes in IW code including:

    __STDCALL macro change to support IPP 2018u3+ external packages
    Memory leak fix in Gaussian filter
    Improved checkers for OpenMP supported features
    Improved declarations for atomic operations.

ICV binary and package version are the same.

3rdparty/ippicv/ippicv.cmake

@@ -2,37 +2,37 @@ function(download_ippicv root_var)
   set(${root_var} "" PARENT_SCOPE)
 
   # Commit SHA in the opencv_3rdparty repo
-  set(IPPICV_COMMIT "dfe3162c237af211e98b8960018b564bc209261d")
+  set(IPPICV_COMMIT "bdb7bb85f34a8cb0d35e40a81f58da431aa1557a")
   # Define actual ICV versions
   if(APPLE)
     set(OPENCV_ICV_PLATFORM "macosx")
     set(OPENCV_ICV_PACKAGE_SUBDIR "ippicv_mac")
     if(X86_64)
-      set(OPENCV_ICV_NAME "ippicv_2017u3_mac_intel64_general_20170822.tgz")
-      set(OPENCV_ICV_HASH "c1ebb5dfa5b7f54b0c44e1917805a463")
+      set(OPENCV_ICV_NAME "ippicv_2017u3_mac_intel64_general_20180518.tgz")
+      set(OPENCV_ICV_HASH "3ae52b9be0fe73dd45bc5e9429cd3732")
     else()
-      set(OPENCV_ICV_NAME "ippicv_2017u3_mac_ia32_general_20170822.tgz")
-      set(OPENCV_ICV_HASH "49b05a669042753ae75895a445ebd612")
+      set(OPENCV_ICV_NAME "ippicv_2017u3_mac_ia32_general_20180518.tgz")
+      set(OPENCV_ICV_HASH "698660b975b62bee3ef6c5af51e97544")
     endif()
   elseif((UNIX AND NOT ANDROID) OR (UNIX AND ANDROID_ABI MATCHES "x86"))
     set(OPENCV_ICV_PLATFORM "linux")
     set(OPENCV_ICV_PACKAGE_SUBDIR "ippicv_lnx")
     if(X86_64)
-      set(OPENCV_ICV_NAME "ippicv_2017u3_lnx_intel64_general_20170822.tgz")
-      set(OPENCV_ICV_HASH "4e0352ce96473837b1d671ce87f17359")
+      set(OPENCV_ICV_NAME "ippicv_2017u3_lnx_intel64_general_20180518.tgz")
+      set(OPENCV_ICV_HASH "b7cc351267db2d34b9efa1cd22ff0572")
     else()
-      set(OPENCV_ICV_NAME "ippicv_2017u3_lnx_ia32_general_20170822.tgz")
-      set(OPENCV_ICV_HASH "dcdb0ba4b123f240596db1840cd59a76")
+      set(OPENCV_ICV_NAME "ippicv_2017u3_lnx_ia32_general_20180518.tgz")
+      set(OPENCV_ICV_HASH "ea72de74dae3c604eb6348395366e78e")
     endif()
   elseif(WIN32 AND NOT ARM)
     set(OPENCV_ICV_PLATFORM "windows")
     set(OPENCV_ICV_PACKAGE_SUBDIR "ippicv_win")
     if(X86_64)
-      set(OPENCV_ICV_NAME "ippicv_2017u3_win_intel64_general_20170822.zip")
-      set(OPENCV_ICV_HASH "0421e642bc7ad741a2236d3ec4190bdd")
+      set(OPENCV_ICV_NAME "ippicv_2017u3_win_intel64_general_20180518.zip")
+      set(OPENCV_ICV_HASH "915ff92958089ede8ea532d3c4fe7187")
     else()
-      set(OPENCV_ICV_NAME "ippicv_2017u3_win_ia32_general_20170822.zip")
-      set(OPENCV_ICV_HASH "8a7680ae352c192de2e2e34936164bd0")
+      set(OPENCV_ICV_NAME "ippicv_2017u3_win_ia32_general_20180518.zip")
+      set(OPENCV_ICV_HASH "928168c2d99ab284047dfcfb7a821d91")
     endif()
   else()
     return()