Index: llvm/trunk/cmake/config-ix.cmake
===================================================================
--- llvm/trunk/cmake/config-ix.cmake
+++ llvm/trunk/cmake/config-ix.cmake
@@ -170,7 +170,8 @@
   check_symbol_exists(siglongjmp setjmp.h HAVE_SIGLONGJMP)
   check_symbol_exists(sigsetjmp setjmp.h HAVE_SIGSETJMP)
 endif()
-if( HAVE_SIGNAL_H )
+// AddressSanitizer conflicts with lib/Support/Unix/Signals.inc
+if( HAVE_SIGNAL_H AND NOT LLVM_USE_SANITIZER MATCHES ".*Address.*")
   check_symbol_exists(sigaltstack signal.h HAVE_SIGALTSTACK)
 endif()
 if( HAVE_SYS_UIO_H )