From d99a9432bcd68eb0c872648965344922eb586afb Mon Sep 17 00:00:00 2001
From: Akash Sharma <akashsharma@cmu.edu>
Date: Fri, 17 Sep 2021 17:59:46 -0400
Subject: [PATCH] Update Find TBB to handle TBB installed with homebrew on OS X
 Better Error message for TBB handling with versions greater than 2021.1 on OS
 X

---
 cmake/FindTBB.cmake   | 16 ++++++++++++++--
 cmake/HandleTBB.cmake |  4 ++++
 2 files changed, 18 insertions(+), 2 deletions(-)

diff --git a/cmake/FindTBB.cmake b/cmake/FindTBB.cmake
index e2b1df6e3b..0ecd4ca0e3 100644
--- a/cmake/FindTBB.cmake
+++ b/cmake/FindTBB.cmake
@@ -144,7 +144,8 @@ if(NOT TBB_FOUND)
 
   elseif(CMAKE_SYSTEM_NAME STREQUAL "Darwin")
     # OS X
-    set(TBB_DEFAULT_SEARCH_DIR "/opt/intel/tbb")
+    set(TBB_DEFAULT_SEARCH_DIR "/opt/intel/tbb"
+                               "/usr/local/opt/tbb")
 
     # TODO: Check to see which C++ library is being used by the compiler.
     if(NOT ${CMAKE_SYSTEM_VERSION} VERSION_LESS 13.0)
@@ -181,7 +182,18 @@ if(NOT TBB_FOUND)
   ##################################
 
   if(TBB_INCLUDE_DIRS)
-    file(READ "${TBB_INCLUDE_DIRS}/tbb/tbb_stddef.h" _tbb_version_file)
+    set(_tbb_version_file_prior_to_tbb_2021_1 "${TBB_INCLUDE_DIRS}/tbb/tbb_stddef.h")
+    set(_tbb_version_file_after_tbb_2021_1 "${TBB_INCLUDE_DIRS}/oneapi/tbb/version.h")
+
+    if (EXISTS "${_tbb_version_file_prior_to_tbb_2021_1}")
+      file(READ "${_tbb_version_file_prior_to_tbb_2021_1}" _tbb_version_file )
+    elseif (EXISTS "${_tbb_version_file_after_tbb_2021_1}")
+      file(READ "${_tbb_version_file_after_tbb_2021_1}" _tbb_version_file )
+    else()
+        message(FATAL_ERROR "Found TBB installation: ${TBB_INCLUDE_DIRS} "
+      "missing version header.")
+    endif()
+
     string(REGEX REPLACE ".*#define TBB_VERSION_MAJOR ([0-9]+).*" "\\1"
         TBB_VERSION_MAJOR "${_tbb_version_file}")
     string(REGEX REPLACE ".*#define TBB_VERSION_MINOR ([0-9]+).*" "\\1"
diff --git a/cmake/HandleTBB.cmake b/cmake/HandleTBB.cmake
index cedee55eaf..e2ba02d941 100644
--- a/cmake/HandleTBB.cmake
+++ b/cmake/HandleTBB.cmake
@@ -5,6 +5,10 @@ find_package(TBB 4.4 COMPONENTS tbb tbbmalloc)
 # Set up variables if we're using TBB
 if(TBB_FOUND AND GTSAM_WITH_TBB)
     set(GTSAM_USE_TBB 1)  # This will go into config.h
+    if ((${TBB_VERSION} VERSION_GREATER "2021.1") OR (${TBB_VERSION} VERSION_EQUAL "2021.1"))
+        message(FATAL_ERROR "TBB version greater than 2021.1 (oneTBB API) is not yet supported. Use an older version instead.")
+    endif()
+
     if ((${TBB_VERSION_MAJOR} GREATER 2020) OR (${TBB_VERSION_MAJOR} EQUAL 2020))
         set(TBB_GREATER_EQUAL_2020 1)
     else()