bpo-46968: Check for 'sys/auxv.h' in the configure script (GH-31961)

Author: pablogsal

Misc/NEWS.d/next/Core and Builtins/2022-03-17-14-22-23.bpo-46968.4gz4NA.rst

@@ -0,0 +1,3 @@
+Check for the existence of the "sys/auxv.h" header in :mod:`faulthandler` to
+avoid compilation problems in systems where this header doesn't exist. Patch
+by Pablo Galindo

Modules/faulthandler.c

@@ -26,9 +26,9 @@
 #  define FAULTHANDLER_USE_ALT_STACK
 #endif
 
-#if defined(FAULTHANDLER_USE_ALT_STACK) && defined(HAVE_LINUX_AUXVEC_H)
-#  include <linux/auxvec.h>
-#  include <sys/auxv.h>
+#if defined(FAULTHANDLER_USE_ALT_STACK) && defined(HAVE_LINUX_AUXVEC_H) && defined(HAVE_SYS_AUXV_H)
+#  include <linux/auxvec.h>       // AT_MINSIGSTKSZ
+#  include <sys/auxv.h>           // getauxval()
 #endif
 
 /* Allocate at maximum 100 MiB of the stack to raise the stack overflow */

configure

@@ -2375,7 +2375,7 @@ AC_DEFINE(STDC_HEADERS, 1, [Define to 1 if you have the ANSI C header files.])
 # checks for header files
 AC_CHECK_HEADERS([ \
   alloca.h asm/types.h bluetooth.h conio.h crypt.h direct.h dlfcn.h endian.h errno.h fcntl.h grp.h \
-  ieeefp.h io.h langinfo.h libintl.h libutil.h linux/auxvec.h linux/memfd.h linux/random.h linux/soundcard.h \
+  ieeefp.h io.h langinfo.h libintl.h libutil.h linux/auxvec.h sys/auxv.h linux/memfd.h linux/random.h linux/soundcard.h \
   linux/tipc.h linux/wait.h netinet/in.h netpacket/packet.h poll.h process.h pthread.h pty.h \
   sched.h setjmp.h shadow.h signal.h spawn.h stropts.h sys/audioio.h sys/bsdtty.h sys/devpoll.h \
   sys/endian.h sys/epoll.h sys/event.h sys/eventfd.h sys/file.h sys/ioctl.h sys/kern_control.h \

configure.ac

@@ -1188,6 +1188,9 @@
 /* Define to 1 if you have the <sys/audioio.h> header file. */
 #undef HAVE_SYS_AUDIOIO_H
 
+/* Define to 1 if you have the <sys/auxv.h> header file. */
+#undef HAVE_SYS_AUXV_H
+
 /* Define to 1 if you have the <sys/bsdtty.h> header file. */
 #undef HAVE_SYS_BSDTTY_H