openwrt报错：[PATCH] cfns: fix mismatch in gnu_inline attributes

gcc的版本太新导致之前的code会报错，有两种解决：
1.就是用gcc-4.7
2.修改code: cfns.gperf和cfns.h
将这一段code分别merge入两个文件
#ifdef __GNUC_STDC_INLINE__ 
__attribute__ ((__gnu_inline__)) 
#endif
达到以下效果：
	* cfns.gperf [__GNUC__, __GNUC_STDC_INLINE__]: Apply the
	__gnu_inline__ attribute.
	* cfns.h: Regenerated.
---
 gcc/cp/cfns.gperf | 3 +++
 gcc/cp/cfns.h     | 3 +++
 2 files changed, 6 insertions(+)

diff --git a/gcc/cp/cfns.gperf b/gcc/cp/cfns.gperf
index 68acd3d..953262f 100644
--- a/gcc/cp/cfns.gperf
+++ b/gcc/cp/cfns.gperf
@@ -22,6 +22,9 @@ __inline
 static unsigned int hash (const char *, unsigned int);
 #ifdef __GNUC__
 __inline
+#ifdef __GNUC_STDC_INLINE__
+__attribute__ ((__gnu_inline__))
+#endif
 #endif
 const char * libc_name_p (const char *, unsigned int);
 %}
diff --git a/gcc/cp/cfns.h b/gcc/cp/cfns.h
index 1c6665d..6d00c0e 100644
--- a/gcc/cp/cfns.h
+++ b/gcc/cp/cfns.h
@@ -53,6 +53,9 @@ __inline
 static unsigned int hash (const char *, unsigned int);
 #ifdef __GNUC__
 __inline
+#ifdef __GNUC_STDC_INLINE__
+__attribute__ ((__gnu_inline__))
+#endif
 #endif
 const char * libc_name_p (const char *, unsigned int);
 /* maximum key range = 391, duplicates = 0 */
-- 
2.4.4

 

原文：

Since the 3.0.3 release of gperf (made in May 2007), the generated func has had the gnu_inline attribute applied to it. The gcc source however has not been updated to include that which has lead to a mismatch. In practice, this hasn't been an issue for two reasons:

(1) Before gcc-5, the default standard was (gnu) C89, and gcc does not warn or throw an error in this mode.

(2) Starting with gcc-4.8, the compiler driver used to build gcc was changed to C++, and g++ does not warn or throw an error in this mode. This error does show up though when using gcc-5 to build gcc-4.7 or older as then the default is (gnu) C11 and the C compiler driver is used.

That failure looks like: In file included from .../gcc-4.7.4/gcc/cp/except.c:990:0: cfns.gperf: At top level: cfns.gperf:101:1: error: 'gnu_inline' attribute present on 'libc_name_p' cfns.gperf:26:14: error: but not here Whether the compiler should always emit this error regardless of the active standard or compiler driver is debatable (I think it should be consistent -- either always do it or never do it). 2015-08-06 Mike Frysinger <[e-mail]>

https://gcc.gnu.org/ml/gcc-patches/2015-08/msg00375.html