When bootstrapping an architecture, it's usual to generate the
kernel's user-space headers (make headers_install) before building a
compiler.  Move the compiler check (for asm goto support) to the
archprepare target so that it is only done when building code for the
target.

Fixes: e501ce957a78 ("x86: Force asm-goto")
Reported-by: Helmut Grohne <helmutg@debian.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
 arch/x86/Makefile | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/arch/x86/Makefile b/arch/x86/Makefile
index 94859241bc3e..7df47ff45f68 100644
--- a/arch/x86/Makefile
+++ b/arch/x86/Makefile
@@ -175,10 +175,6 @@ ifdef CONFIG_FUNCTION_GRAPH_TRACER
   endif
 endif
 
-ifndef CC_HAVE_ASM_GOTO
-  $(error Compiler lacks asm-goto support.)
-endif
-
 #
 # Jump labels need '-maccumulate-outgoing-args' for gcc < 4.5.2 to prevent a
 # GCC bug (https://gcc.gnu.org/bugzilla/show_bug.cgi?id=46226).  There's no way
@@ -312,6 +308,13 @@ PHONY += vdso_install
 vdso_install:
 	$(Q)$(MAKE) $(build)=arch/x86/entry/vdso $@
 
+archprepare: checkbin
+checkbin:
+ifndef CC_HAVE_ASM_GOTO
+	@echo Compiler lacks asm-goto support.
+	@exit 1
+endif
+
 archclean:
 	$(Q)rm -rf $(objtree)/arch/i386
 	$(Q)rm -rf $(objtree)/arch/x86_64