[glibc/maskray/clang] Disable __USE_EXTERN_INLINES for clang

[Fangrui Song]

https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=425c5b3402901b13fcab3f9d775754e411f09153

commit 425c5b3402901b13fcab3f9d775754e411f09153
Author: Fangrui Song <maskray@google.com>
Date:   Thu Oct 7 18:16:04 2021 -0700

    Disable __USE_EXTERN_INLINES for clang

Diff:
---
 include/features.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/features.h b/include/features.h
index d974eabfaf..11cbbf512a 100644
--- a/include/features.h
+++ b/include/features.h
@@ -500,7 +500,7 @@
 /* Decide whether we can define 'extern inline' functions in headers.  */
 #if __GNUC_PREREQ (2, 7) && defined __OPTIMIZE__ \
     && !defined __OPTIMIZE_SIZE__ && !defined __NO_INLINE__ \
-    && defined __extern_inline
+    && defined __extern_inline && !defined __clang__
 # define __USE_EXTERN_INLINES	1
 #endif