diff --git a/clang/CMakeLists.txt b/clang/CMakeLists.txt
--- a/clang/CMakeLists.txt
+++ b/clang/CMakeLists.txt
@@ -517,7 +517,10 @@
 
 # All targets below may depend on all tablegen'd files.
 get_property(CLANG_TABLEGEN_TARGETS GLOBAL PROPERTY CLANG_TABLEGEN_TARGETS)
-add_custom_target(clang-tablegen-targets DEPENDS ${CLANG_TABLEGEN_TARGETS})
+add_custom_target(clang-tablegen-targets
+  DEPENDS
+  omp_gen
+  ${CLANG_TABLEGEN_TARGETS})
 set_target_properties(clang-tablegen-targets PROPERTIES FOLDER "Misc")
 list(APPEND LLVM_COMMON_DEPENDS clang-tablegen-targets)