autotools ac_check_member宏不适用于Linux内核结构

Question

如果Linux内核结构（称为task_struct）在其中是否有成员变量__STATE，我想定义一个自动工具变量。此结构在Inclubple/linux/sched.h中定义。我还尝试检查该结构中的其他成员变量（例如flags），但无济于事。

我可以将ac_check_member宏用于struct blk_zone.capacity（如下所示）并获得正确的结果。

我的裸露骨头配置。AC文件重现这一点是：

AC_INIT(hello-1.c)
CPPFLAGS="-I/usr/src/kernels/4.18.0-372.9.1.el8.x86_64"

AC_CHECK_MEMBER([struct task_struct.__state],
        [AC_DEFINE(WE_HAVE_STATE, [1], [__state member var was found])],
        [], [[#include <linux/sched.h>]])
AC_CHECK_MEMBER([struct blk_zone.capacity],
                [AC_DEFINE(HAVE_BLK_ZONE_REP_V2, [1], [report zones includes zone capacity])],
                [], [[#include <linux/blkzoned.h>]])
AC_CONFIG_FILES([Makefile])
AC_OUTPUT

我的config.log文件似乎在说文件中没有构造。任何帮助将不胜感激！

configure:2574: checking for struct task_struct.__state
configure:2574: gcc -c -g -O2 -I/usr/src/kernels/4.18.0-372.9.1.el8.x86_64 conftest.c >&5
conftest.c: In function 'main':
conftest.c:14:27: error: storage size of 'ac_aggr' isn't known
 static struct task_struct ac_aggr;
                           ^~~~~~~
configure:2574: $? = 1
configure: failed program was:
| /* confdefs.h */
| #define PACKAGE_NAME ""
| #define PACKAGE_TARNAME ""
| #define PACKAGE_VERSION ""
| #define PACKAGE_STRING ""
| #define PACKAGE_BUGREPORT ""
| #define PACKAGE_URL ""
| /* end confdefs.h.  */
| #include <linux/sched.h>
| 
| int
| main ()
| {
| static struct task_struct ac_aggr;
| if (ac_aggr.__state)
| return 0;
|   ;
|   return 0;
| }
configure:2574: gcc -c -g -O2 -I/usr/src/kernels/4.18.0-372.9.1.el8.x86_64 conftest.c >&5
conftest.c: In function 'main':
conftest.c:14:27: error: storage size of 'ac_aggr' isn't known
 static struct task_struct ac_aggr;
                           ^~~~~~~
configure:2574: $? = 1
configure: failed program was:
| /* confdefs.h */
| #define PACKAGE_NAME ""
| #define PACKAGE_TARNAME ""
| #define PACKAGE_VERSION ""
| #define PACKAGE_STRING ""
| #define PACKAGE_BUGREPORT ""
| #define PACKAGE_URL ""
| /* end confdefs.h.  */
| #include <linux/sched.h>
| 
| int
| main ()
| {
| static struct task_struct ac_aggr;
| if (sizeof ac_aggr.__state)
| return 0;
|   ;
|   return 0;
| }
configure:2574: result: no
configure:2582: checking for struct blk_zone.capacity
configure:2582: gcc -c -g -O2 -I/usr/src/kernels/4.18.0-372.9.1.el8.x86_64 conftest.c >&5
configure:2582: $? = 0
configure:2582: result: yes
configure:2742: creating ./config.status


```                           ^~~~~~~