diff --git a/gdb/ax-general.c b/gdb/ax-general.c
index 05ca556703e..0c767c1c0df 100644
--- a/gdb/ax-general.c
+++ b/gdb/ax-general.c
@@ -232,7 +232,8 @@ ax_reg (struct agent_expr *x, int reg)
 	error (_("'%s' is a pseudo-register; "
 		 "GDB cannot yet trace its contents."),
 	       user_reg_map_regnum_to_name (x->gdbarch, reg));
-      if (gdbarch_ax_pseudo_register_push_stack (x->gdbarch, x, reg))
+
+      if (!gdbarch_ax_pseudo_register_push_stack (x->gdbarch, x, reg))
 	error (_("Trace '%s' failed."),
 	       user_reg_map_regnum_to_name (x->gdbarch, reg));
     }
diff --git a/gdb/gdbarch-gen.c b/gdb/gdbarch-gen.c
index c4da3fa4c29..e622e812de5 100644
--- a/gdb/gdbarch-gen.c
+++ b/gdb/gdbarch-gen.c
@@ -1974,7 +1974,7 @@ gdbarch_ax_pseudo_register_push_stack_p (struct gdbarch *gdbarch)
   return gdbarch->ax_pseudo_register_push_stack != NULL;
 }
 
-int
+bool
 gdbarch_ax_pseudo_register_push_stack (struct gdbarch *gdbarch, struct agent_expr *ax, int reg)
 {
   gdb_assert (gdbarch != NULL);
diff --git a/gdb/gdbarch-gen.h b/gdb/gdbarch-gen.h
index 13e9b94a8ff..b0534c3e6ab 100644
--- a/gdb/gdbarch-gen.h
+++ b/gdb/gdbarch-gen.h
@@ -246,12 +246,13 @@ extern void set_gdbarch_ax_pseudo_register_collect (struct gdbarch *gdbarch, gdb
 
 /* Assemble agent expression bytecode to push the value of pseudo-register
    REG on the interpreter stack.
-   Return -1 if something goes wrong, 0 otherwise. */
+   REG must be a valid register number.
+   Return false if something goes wrong, true otherwise. */
 
 extern bool gdbarch_ax_pseudo_register_push_stack_p (struct gdbarch *gdbarch);
 
-typedef int (gdbarch_ax_pseudo_register_push_stack_ftype) (struct gdbarch *gdbarch, struct agent_expr *ax, int reg);
-extern int gdbarch_ax_pseudo_register_push_stack (struct gdbarch *gdbarch, struct agent_expr *ax, int reg);
+typedef bool (gdbarch_ax_pseudo_register_push_stack_ftype) (struct gdbarch *gdbarch, struct agent_expr *ax, int reg);
+extern bool gdbarch_ax_pseudo_register_push_stack (struct gdbarch *gdbarch, struct agent_expr *ax, int reg);
 extern void set_gdbarch_ax_pseudo_register_push_stack (struct gdbarch *gdbarch, gdbarch_ax_pseudo_register_push_stack_ftype *ax_pseudo_register_push_stack);
 
 /* Some architectures can display additional information for specific
diff --git a/gdb/gdbarch_components.py b/gdb/gdbarch_components.py
index 4c51dc3d04c..3dead483934 100644
--- a/gdb/gdbarch_components.py
+++ b/gdb/gdbarch_components.py
@@ -498,9 +498,10 @@ Method(
     comment="""
 Assemble agent expression bytecode to push the value of pseudo-register
 REG on the interpreter stack.
-Return -1 if something goes wrong, 0 otherwise.
+REG must be a valid register number.
+Return false if something goes wrong, true otherwise.
 """,
-    type="int",
+    type="bool",
     name="ax_pseudo_register_push_stack",
     params=[("struct agent_expr *", "ax"), ("int", "reg")],
     predicate=True,
diff --git a/gdb/mips-tdep.c b/gdb/mips-tdep.c
index 0babb8b9b98..82fa67e7055 100644
--- a/gdb/mips-tdep.c
+++ b/gdb/mips-tdep.c
@@ -841,7 +841,7 @@ mips_ax_pseudo_register_collect (struct gdbarch *gdbarch,
   ax_reg_mask (ax, rawnum);
 }
 
-static int
+static bool
 mips_ax_pseudo_register_push_stack (struct gdbarch *gdbarch,
 				    struct agent_expr *ax, int reg)
 {
@@ -870,7 +870,7 @@ mips_ax_pseudo_register_push_stack (struct gdbarch *gdbarch,
   else
     internal_error (_("bad register size"));
 
-  return 0;
+  return true;
 }
 
 /* Table to translate 3-bit register field to actual register number.  */
diff --git a/gdb/s390-tdep.c b/gdb/s390-tdep.c
index 8a3bde525e9..ab00b65d640 100644
--- a/gdb/s390-tdep.c
+++ b/gdb/s390-tdep.c
@@ -1536,7 +1536,7 @@ s390_ax_pseudo_register_collect (struct gdbarch *gdbarch,
 
 /* The "ax_pseudo_register_push_stack" gdbarch method.  */
 
-static int
+static bool
 s390_ax_pseudo_register_push_stack (struct gdbarch *gdbarch,
 				    struct agent_expr *ax, int regnum)
 {
@@ -1571,13 +1571,13 @@ s390_ax_pseudo_register_push_stack (struct gdbarch *gdbarch,
   else if (regnum_is_vxr_full (tdep, regnum))
     {
       /* Too large to stuff on the stack.  */
-      return 1;
+      return false;
     }
   else
     {
       internal_error (_("invalid regnum"));
     }
-  return 0;
+  return true;
 }
 
 /* The "gen_return_address" gdbarch method.  Since this is supposed to be