diff --git a/README.md b/README.md
index adeb36bb..fa5cef68 100644
--- a/README.md
+++ b/README.md
@@ -1083,37 +1083,39 @@ Please note:
 
 The following compilers are currently used in continuous integration at [Travis](https://travis-ci.org/nlohmann/json), [AppVeyor](https://ci.appveyor.com/project/nlohmann/json), [GitHub Actions](https://github.com/nlohmann/json/actions), and [CircleCI](https://circleci.com/gh/nlohmann/json):
 
-| Compiler                   | Operating System         | CI Provider    |
-|----------------------------|--------------------------|----------------|
-| AppleClang 9.1.0.9020039   | Darwin-17.4.0            | Travis         |
-| AppleClang 9.1.0.9020039   | Darwin-17.7.0            | Travis         |
-| AppleClang 10.0.0.10001145 | Darwin-17.7.0            | Travis         |
-| AppleClang 10.0.1.10010046 | Darwin-18.5.0            | Travis         |
-| AppleClang 11.0.0.11000033 | Darwin-18.7.0            | Travis         |
-| AppleClang 11.0.3.11030032 | Darwin-19.4.0            | GitHub Actions |
-| Clang 3.5.0                | Linux-4.4.0-104-generic  | Travis         |
-| Clang 3.6.2                | Linux-4.4.0-104-generic  | Travis         |
-| Clang 3.7.1                | Linux-4.4.0-104-generic  | Travis         |
-| Clang 3.8.0                | Linux-4.4.0-104-generic  | Travis         |
-| Clang 3.9.1                | Linux-4.4.0-104-generic  | Travis         |
-| Clang 4.0.1                | Linux-4.4.0-104-generic  | Travis         |
-| Clang 5.0.2                | Linux-4.4.0-104-generic  | Travis         |
-| Clang 6.0.1                | Linux-4.4.0-104-generic  | Travis         |
-| Clang 7.1.0                | Linux-4.4.0-104-generi   | Travis         |
-| GNU 4.8.5                  | Linux-4.4.0-104-generic  | Travis         |
-| GNU 4.9.4                  | Linux-4.4.0-104-generic  | Travis         |
-| GNU 5.5.0                  | Linux-4.4.0-104-generic  | Travis         |
-| GNU 6.3.0                  | Linux-5.3.0-1017-aws     | Circle CI      |
-| GNU 6.5.0                  | Linux-4.4.0-104-generic  | Travis         |
-| GNU 7.3.0 (MinGW)          | Windows-6.3.9600         | AppVeyor       |
-| GNU 7.5.0                  | Linux-4.4.0-104-generic  | Travis         |
-| GNU 7.5.0                  | Linux-5.3.0-1020-azure   | GitHub Actions |
-| GNU 8.4.0                  | Linux-4.4.0-104-generic  | Travis         |
-| GNU 9.3.0                  | Linux-4.4.0-104-generic  | Travis         |
-| MSVC 19.0.24241.7          | Windows-6.3.9600         | AppVeyor       |
-| MSVC 19.16.27035.0         | Windows-10.0.14393       | AppVeyor       |
-| MSVC 19.25.28614.0         | Windows-10.0.17763       | AppVeyor       |
-| MSVC 19.25.28614.0         | Windows-10.0.17763       | GitHub Actions |
+| Compiler                                                        | Operating System   | CI Provider    |
+|-----------------------------------------------------------------|--------------------|----------------|
+| Apple Clang 9.1.0 (clang-902.0.39.1); Xcode 9.3                 | macOS 10.13.3      | Travis         |
+| Apple Clang 9.1.0 (clang-902.0.39.2); Xcode 9.4.1               | macOS 10.13.6      | Travis         |
+| Apple Clang 10.0.0 (clang-1000.11.45.2); Xcode 10.0             | macOS 10.13.6      | Travis         |
+| Apple Clang 10.0.0 (clang-1000.11.45.5); Xcode 10.1             | macOS 10.13.6      | Travis         |
+| Apple Clang 10.0.1 (clang-1001.0.46.4); Xcode 10.2.1            | macOS 10.14.4      | Travis         |
+| Apple Clang 11.0.0 (clang-1100.0.33.12); Xcode 11.2.1           | macOS 10.14.6      | Travis         |
+| Apple Clang 11.0.3 (clang-1103.0.32.59); Xcode 11.4.1           | macOS 10.15.4      | GitHub Actions |
+| Clang 3.5.0 (3.5.0-4ubuntu2~trusty2)                            | Ubuntu 14.04.5 LTS | Travis         |
+| Clang 3.6.2 (3.6.2-svn240577-1~exp1)                            | Ubuntu 14.04.5 LTS | Travis         |
+| Clang 3.7.1 (3.7.1-svn253571-1~exp1)                            | Ubuntu 14.04.5 LTS | Travis         |
+| Clang 3.8.0 (3.8.0-2ubuntu3~trusty5)                            | Ubuntu 14.04.5 LTS | Travis         |
+| Clang 3.9.1 (3.9.1-4ubuntu3~14.04.3)                            | Ubuntu 14.04.5 LTS | Travis         |
+| Clang 4.0.1 (4.0.1-svn305264-1~exp1)                            | Ubuntu 14.04.5 LTS | Travis         |
+| Clang 5.0.2 (version 5.0.2-svn328729-1~exp1~20180509123505.100) | Ubuntu 14.04.5 LTS | Travis         |
+| Clang 6.0.1 (6.0.1-svn334776-1~exp1~20190309042707.121)         | Ubuntu 14.04.5 LTS | Travis         |
+| Clang 7.1.0 (7.1.0-svn353565-1~exp1~20190419134007.64)          | Ubuntu 14.04.5 LTS | Travis         |
+| Clang 7.5.0 (Ubuntu 7.5.0-3ubuntu1~18.04)                       | Ubuntu 18.04.4 LTS | Travis         |
+| GCC 4.8.5 (Ubuntu 4.8.5-4ubuntu8~14.04.2)                       | Ubuntu 14.04.5 LTS | Travis         |
+| GCC 4.9.4 (Ubuntu 4.9.4-2ubuntu1~14.04.1)                       | Ubuntu 14.04.5 LTS | Travis         |
+| GCC 5.5.0 (Ubuntu 5.5.0-12ubuntu1~14.04)                        | Ubuntu 14.04.5 LTS | Travis         |
+| GCC 6.3.0 (Debian 6.3.0-18+deb9u1)                              | Debian 9           | Circle CI      |
+| GCC 6.5.0 (Ubuntu 6.5.0-2ubuntu1~14.04.1)                       | Ubuntu 14.04.5 LTS | Travis         |
+| GCC 7.3.0 (x86_64-posix-seh-rev0, Built by MinGW-W64 project)   | Windows-6.3.9600   | AppVeyor       |
+| GCC 7.5.0 (Ubuntu 7.5.0-3ubuntu1~14.04.1)                       | Ubuntu 14.04.5 LTS | Travis         |
+| GCC 7.5.0 (Ubuntu 7.5.0-3ubuntu1~18.04)                         | Ubuntu 18.04.4 LTS | GitHub Actions |
+| GCC 8.4.0 (Ubuntu 8.4.0-1ubuntu1~14.04)                         | Ubuntu 14.04.5 LTS | Travis         |
+| GCC 9.3.0 (Ubuntu 9.3.0-11ubuntu0~14.04)                        | Ubuntu 14.04.5 LTS | Travis         |
+| MSVC 19.0.24241.7 (Build Engine version 14.0.25420.1)           | Windows-6.3.9600   | AppVeyor       |
+| MSVC 19.16.27035.0 (15.9.21+g9802d43bc3 for .NET Framework)     | Windows-10.0.14393 | AppVeyor       |
+| MSVC 19.25.28614.0 (Build Engine version 16.5.0+d4cbfca49 for .NET Framework) | Windows-10.0.17763  | AppVeyor       |
+| MSVC 19.25.28614.0 (Build Engine version 16.5.0+d4cbfca49 for .NET Framework) | Windows-10.0.17763  | GitHub Actions |
 
 ## License
 
diff --git a/cmake/download_test_data.cmake b/cmake/download_test_data.cmake
index 0940382a..53aef17f 100644
--- a/cmake/download_test_data.cmake
+++ b/cmake/download_test_data.cmake
@@ -24,17 +24,17 @@ if (VER_COMMAND)
     set(OS_VERSION_STRINGS "${OS_VERSION_STRINGS}; ${VER_COMMAND_RESULT}")
 endif()
 if (SW_VERS_COMMAND)
-    execute_process(COMMAND ${SW_VERS_COMMAND} OUTPUT_VARIABLE SW_VERS_COMMAND_RESULT OUTPUT_STRIP_TRAILING_WHITESPACE)
+    execute_process(COMMAND ${SW_VERS_COMMAND} OUTPUT_VARIABLE SW_VERS_COMMAND_RESULT OUTPUT_STRIP_TRAILING_WHITESPACE ERROR_QUIET)
     string(REGEX REPLACE "[ ]*\n" "; " SW_VERS_COMMAND_RESULT "${SW_VERS_COMMAND_RESULT}")
     set(OS_VERSION_STRINGS "${OS_VERSION_STRINGS}; ${SW_VERS_COMMAND_RESULT}")
 endif()
 if (LSB_RELEASE_COMMAND)
-    execute_process(COMMAND ${LSB_RELEASE_COMMAND} -a OUTPUT_VARIABLE LSB_RELEASE_COMMAND_RESULT OUTPUT_STRIP_TRAILING_WHITESPACE)
+    execute_process(COMMAND ${LSB_RELEASE_COMMAND} -a OUTPUT_VARIABLE LSB_RELEASE_COMMAND_RESULT OUTPUT_STRIP_TRAILING_WHITESPACE ERROR_QUIET)
     string(REGEX REPLACE "[ ]*\n" "; " LSB_RELEASE_COMMAND_RESULT "${LSB_RELEASE_COMMAND_RESULT}")
     set(OS_VERSION_STRINGS "${OS_VERSION_STRINGS}; ${LSB_RELEASE_COMMAND_RESULT}")
 endif()
 if (UNAME_COMMAND)
-    execute_process(COMMAND ${UNAME_COMMAND} -a OUTPUT_VARIABLE UNAME_COMMAND_RESULT OUTPUT_STRIP_TRAILING_WHITESPACE)
+    execute_process(COMMAND ${UNAME_COMMAND} -a OUTPUT_VARIABLE UNAME_COMMAND_RESULT OUTPUT_STRIP_TRAILING_WHITESPACE ERROR_QUIET)
     set(OS_VERSION_STRINGS "${OS_VERSION_STRINGS}; ${UNAME_COMMAND_RESULT}")
 endif()