Add UR_ENABLE_ASSERTIONS flag for enabling asserts on all build types.

Author: aarongreig

CMakeLists.txt

@@ -47,6 +47,9 @@ option(VAL_USE_LIBBACKTRACE_BACKTRACE "enable libbacktrace validation backtrace
 set(UR_DPCXX "" CACHE FILEPATH "Path of the DPC++ compiler executable")
 set(UR_SYCL_LIBRARY_DIR "" CACHE PATH
     "Path of the SYCL runtime library directory")
+option(UR_ENABLE_ASSERTIONS "Enable assertions for all build types" OFF)
+
+include(Assertions)
 
 set(CMAKE_LIBRARY_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/lib)
 set(CMAKE_ARCHIVE_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/lib)

cmake/Assertions.cmake

@@ -0,0 +1,30 @@
+# From the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+# See https://llvm.org/LICENSE.txt for license information.
+# SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+
+# This is lifted from llvm's LLVM_ENABLE_ASSERTIONS implementation
+# https://github.com/llvm/llvm-project/blob/6be0e979896f7dd610abf263f845c532f1be3762/llvm/cmake/modules/HandleLLVMOptions.cmake#L89
+if(UR_ENABLE_ASSERTIONS)
+  # MSVC doesn't like _DEBUG on release builds
+  if( NOT MSVC )
+    add_compile_definitions(_DEBUG)
+  endif()
+  # On non-Debug builds cmake automatically defines NDEBUG, so we
+  # explicitly undefine it:
+  if( NOT uppercase_CMAKE_BUILD_TYPE STREQUAL "DEBUG" )
+    add_compile_options($<$<OR:$<COMPILE_LANGUAGE:C>,$<COMPILE_LANGUAGE:CXX>>:-UNDEBUG>)
+    if (MSVC)
+      # Also remove /D NDEBUG to avoid MSVC warnings about conflicting defines.
+      foreach (flags_var_to_scrub
+          CMAKE_CXX_FLAGS_RELEASE
+          CMAKE_CXX_FLAGS_RELWITHDEBINFO
+          CMAKE_CXX_FLAGS_MINSIZEREL
+          CMAKE_C_FLAGS_RELEASE
+          CMAKE_C_FLAGS_RELWITHDEBINFO
+          CMAKE_C_FLAGS_MINSIZEREL)
+        string (REGEX REPLACE "(^| )[/-]D *NDEBUG($| )" " "
+          "${flags_var_to_scrub}" "${${flags_var_to_scrub}}")
+      endforeach()
+    endif()
+  endif()
+endif()