We need -lexecinfo. Use the static version for ease.

Index: runtime/flangrti/CMakeLists.txt
--- runtime/flangrti/CMakeLists.txt.orig
+++ runtime/flangrti/CMakeLists.txt
@@ -93,6 +93,9 @@ find_library( 
   HINTS ${CMAKE_BINARY_DIR}/lib)
 target_link_libraries(flangrti_shared ${LIBPGMATH})
 
+# Import execinfo
+target_link_libraries(flangrti_shared ${FLANG_LIBEXECINFO})
+
 if( ${TARGET_ARCHITECTURE} STREQUAL "aarch64" )
   target_compile_definitions(flangrti_static PRIVATE TARGET_LINUX_ARM)
   target_compile_definitions(flangrti_shared PRIVATE TARGET_LINUX_ARM)
