Merge pull request ceph#62663 from adamemerson/wip-tbb-O0

build: Pull TBB into `$EXTRALIBS` if it is available

Reviewed-by: Kefu Chai <[email protected]>

Author: adamemerson

src/common/io_exerciser/CMakeLists.txt

@@ -12,4 +12,17 @@ target_link_libraries(object_io_exerciser
   librados
   global
   json_structures
-)
+)
+
+# libstdc++ uses TBB to implement <execution> if it is available,
+# which means that if we're going to use <execution>, we need to link
+# against TBB if it's available.
+#
+# It happens to work by accident at present because the optimizer
+# optimizes out our one reference, for now, but this breaks compiling
+# with `-O0` and will break anyway once we try to do more.
+find_package(TBB QUIET)
+if(TBB_FOUND)
+  message(STATUS "Linking to TBB for implementations of <execution>.")
+  target_link_libraries(object_io_exerciser TBB::tbb)
+endif(TBB_FOUND)