[gdbserver] disable Elf32_auxv_t/Elf64_auxv_t AC_CHECK_TYPES check on Android

See the comment added in configure.ac for more details behind
this change.

gdb/gdbserver/ChangeLog:

        * configure.ac: Do not call AC_CHECK_TYPES for Elf32_auxv_t
        and Elf64_auxv_t if the target is Android.

1 files changed, 17 insertions, 3 deletions

diff --git a/gdb/gdbserver/configure.ac b/gdb/gdbserver/configure.ac
index d50d0f1..5524a05 100644
--- a/gdb/gdbserver/configure.ac
+++ b/gdb/gdbserver/configure.ac
@@ -235,9 +235,23 @@ AC_CHECK_TYPES(socklen_t, [], [],
 #include <sys/socket.h>
 ])
 
-AC_CHECK_TYPES([Elf32_auxv_t, Elf64_auxv_t], [], [],
-#include <elf.h>
-)
+case "${target}" in
+  *-android*)
+    # Starting with NDK version 9, <elf.h> actually includes definitions
+    # of Elf32_auxv_t and Elf64_auxv_t. But sadly, <elf.h> includes
+    # <sys/exec_elf.h> which defines some of the ELF types incorrectly,
+    # leading to conflicts with the defintions from <linux/elf.h>.
+    # This makes it impossible for us to include both <elf.h> and
+    # <linux/elf.h>, which means that, in practice, we do not have
+    # access to Elf32_auxv_t and Elf64_auxv_t on this platform.
+    # Therefore, do not try to auto-detect availability, as it would
+    # get it wrong on this platform.
+    ;;
+  *)
+    AC_CHECK_TYPES([Elf32_auxv_t, Elf64_auxv_t], [], [],
+    #include <elf.h>
+    )
+esac
 
 ACX_PKGVERSION([GDB])
 ACX_BUGURL([http://www.gnu.org/software/gdb/bugs/])