diff --git a/compiler-rt/lib/builtins/cpu_model.c b/compiler-rt/lib/builtins/cpu_model.c
--- a/compiler-rt/lib/builtins/cpu_model.c
+++ b/compiler-rt/lib/builtins/cpu_model.c
@@ -924,6 +924,9 @@
 #define HWCAP_SB (1 << 29)
 #endif
 
+#ifndef AT_HWCAP2
+#define AT_HWCAP2 26
+#endif
 #ifndef HWCAP2_DCPODP
 #define HWCAP2_DCPODP (1 << 0)
 #endif