diff --git a/package/gcc/gcc.mk b/package/gcc/gcc.mk
index e34801390b..b58f17575a 100644
--- a/package/gcc/gcc.mk
+++ b/package/gcc/gcc.mk
@@ -138,6 +138,14 @@ ifeq ($(BR2_sparc)$(BR2_sparc64),y)
 HOST_GCC_COMMON_CONF_OPTS += --disable-libsanitizer
 endif
 
+# The logic in libbacktrace/configure.ac to detect if __sync builtins
+# are available assumes they are as soon as target_subdir is not
+# empty, i.e when cross-compiling. However, some platforms do not have
+# __sync builtins, so help the configure script a bit.
+ifeq ($(BR2_TOOLCHAIN_HAS_SYNC_4),)
+HOST_GCC_COMMON_CONF_ENV += target_configargs="libbacktrace_cv_sys_sync=no"
+endif
+
 # TLS support is not needed on uClibc/no-thread and
 # uClibc/linux-threads, otherwise, for all other situations (glibc,
 # musl and uClibc/NPTL), we need it.