From: Michael Wallner <mike@php.net>
Date: Fri, 11 Dec 2020 09:27:47 +0000 (+0100)
Subject: cmake: better check for CPP17 parallelism
X-Git-Tag: 1.1.0-beta1~69
X-Git-Url: https://git.m6w6.name/?p=m6w6%2Flibmemcached;a=commitdiff_plain;h=f875d401486e0e12d30b28e9d62220fdf6cd8561

cmake: better check for CPP17 parallelism
---

diff --git a/CMake/CheckCpp17Parallelism.cmake b/CMake/CheckCpp17Parallelism.cmake
new file mode 100644
index 00000000..cc3f0d2a
--- /dev/null
+++ b/CMake/CheckCpp17Parallelism.cmake
@@ -0,0 +1,30 @@
+configure_define(HAVE_CPP17_PARALLELISM)
+
+#
+# see CheckTbb.cmake on change
+#
+
+check_cxx_source_compiles("
+                #include <vector>
+                #include <algorithm>
+                #include <execution>
+                int main() {
+                    std::vector<char> a = {1,2,3};
+                    std::all_of(std::execution::par, a.begin(), a.end(), [](char i) {
+                        return i>0;
+                    });
+                }
+                "
+        HAVE_CPP17_PARALLELISM
+        )
+
+if(HAVE_CPP17_PARALLELISM)
+    add_library(cpp17::paralleslism INTERFACE IMPORTED)
+    # noting to be done
+else()
+    include(CheckTbb)
+    set(HAVE_CPP17_PARALLELISM "${HAVE_TBB}")
+    if(HAVE_TBB)
+        add_library(cpp17::parallelism ALIAS "${LIBTBB}")
+    endif()
+endif()
diff --git a/CMake/CheckTbb.cmake b/CMake/CheckTbb.cmake
index b3ea50f4..cd76ab3e 100644
--- a/CMake/CheckTbb.cmake
+++ b/CMake/CheckTbb.cmake
@@ -27,7 +27,8 @@ if(HAVE_LIBTBB)
                 }
                 "
                 HAVE_TBB
-        )
+                )
+
     endif()
     cmake_pop_check_state()
 endif()
diff --git a/test/CMakeLists.txt b/test/CMakeLists.txt
index 1f86466a..6e64777a 100644
--- a/test/CMakeLists.txt
+++ b/test/CMakeLists.txt
@@ -60,10 +60,10 @@ target_link_libraries(runtests PRIVATE libhashkit libmemcachedinternal libmemcac
 
 # parallelism
 if(NOT (thread IN_LIST ENABLE_SANITIZERS))
-    include(CheckTbb)
-endif()
-if(HAVE_TBB)
-    target_link_libraries(runtests PRIVATE ${LIBTBB})
+    include(CheckCpp17Parallelism)
+    if(HAVE_CPP17_PARALLELISM)
+        target_link_libraries(runtests PRIVATE cpp17::parallelism)
+    endif()
 endif()
 
 add_dependencies(runtests ${CLIENTS})