diff --git a/llvm/CMakeLists.txt b/llvm/CMakeLists.txt
--- a/llvm/CMakeLists.txt
+++ b/llvm/CMakeLists.txt
@@ -402,7 +402,6 @@
 
 set(LLVM_ENABLE_Z3_SOLVER_DEFAULT "${Z3_FOUND}")
 
-
 if( LLVM_TARGETS_TO_BUILD STREQUAL "all" )
   set( LLVM_TARGETS_TO_BUILD ${LLVM_ALL_TARGETS} )
 endif()
diff --git a/llvm/cmake/config-ix.cmake b/llvm/cmake/config-ix.cmake
--- a/llvm/cmake/config-ix.cmake
+++ b/llvm/cmake/config-ix.cmake
@@ -159,6 +159,27 @@
   set(LLVM_ENABLE_LIBXML2 "${HAVE_LIBXML2}")
 endif()
 
+if(LLVM_ENABLE_CURL)
+  if(LLVM_ENABLE_CURL STREQUAL FORCE_ON)
+    find_package(CURL REQUIRED)
+  else()
+    find_package(CURL)
+  endif()
+  if(CURL_FOUND)
+    # Check if curl we found is usable; for example, we may have found a 32-bit
+    # library on a 64-bit system which would result in a link-time failure.
+    cmake_push_check_state()
+    list(APPEND CMAKE_REQUIRED_INCLUDES ${CURL_INCLUDE_DIRS})
+    list(APPEND CMAKE_REQUIRED_LIBRARIES ${CURL_LIBRARY})
+    check_symbol_exists(curl_easy_init curl.h HAVE_CURL)
+    cmake_pop_check_state()
+    if(LLVM_ENABLE_CURL STREQUAL FORCE_ON AND NOT HAVE_CURL)
+      message(FATAL_ERROR "Failed to configure curl")
+    endif()
+  endif()
+  set(LLVM_ENABLE_CURL "${HAVE_CURL}")
+endif()
+
 # Don't look for these libraries if we're using MSan, since uninstrumented third
 # party code may call MSan interceptors like strlen, leading to false positives.
 if(NOT LLVM_USE_SANITIZER MATCHES "Memory.*")