Fix aarch64-freebsd build failure

[deliverable/binutils-gdb.git] / gdb / amd64-nat.c

diff --git a/gdb/amd64-nat.c b/gdb/amd64-nat.c
index 884f04d986dc88273559edc83865a072550809cc..ff0433997ea4e6bb3c559da13838b0e1212b77b5 100644 (file)
--- a/gdb/amd64-nat.c
+++ b/gdb/amd64-nat.c
@@ -1,6 +1,6 @@
 /* Native-dependent code for AMD64.
 
-   Copyright (C) 2003-2015 Free Software Foundation, Inc.
+   Copyright (C) 2003-2017 Free Software Foundation, Inc.
 
    This file is part of GDB.
 
@@ -65,10 +65,17 @@ amd64_native_gregset_reg_offset (struct gdbarch *gdbarch, int regnum)
   if (num_regs > gdbarch_num_regs (gdbarch))
     num_regs = gdbarch_num_regs (gdbarch);
 
-  if (regnum < num_regs && regnum < gdbarch_num_regs (gdbarch))
-    return reg_offset[regnum];
+  if (regnum >= num_regs)
+    return -1;
 
-  return -1;
+  /* Kernels that predate Linux 2.6.25 don't provide access to
+     these segment registers in user_regs_struct.   */
+#ifndef HAVE_STRUCT_USER_REGS_STRUCT_FS_BASE
+  if (regnum == AMD64_FSBASE_REGNUM || regnum == AMD64_GSBASE_REGNUM)
+    return -1;
+#endif
+
+  return reg_offset[regnum];
 }
 
 /* Return whether the native general-purpose register set supplies