[RFA] Define Elf32_auxv_t and Elf64_auxv_t if not available.

[Thiago Jung Bauermann <thiago.bauermann@linaro.org>]

Hi,

glibc's <elf.h> says this about Elf32_auxv_t and Elf64_auxv_t:

   The vector is not usually defined in a standard <elf.h> file, but it
   can't hurt.  We rename it to avoid conflicts.

Android's bionic libc doesn't define these types in <elf.h>. To be
honest I couldn't find a definition for auxv_t in ARM's EABI and I'm not
aware of an Android EABI document. I confirmed that bionic internally
uses this format though, and this definition seems unlikely to change.

Ok to commit? It doesn't affect compilation in i386-linux or
armv5tel-linux-gnueabi.
-- 
[]'s
Thiago Jung Bauermann
Linaro Toolchain Working Group


2012-03-26  Thiago Jung Bauermann  <thiago.bauermann@linaro.org>

	* configure.ac: Check whether Elf32_auxv_t and Elf64_auxv_t
	are available.
	* linux-low.c [HAVE_ELF32_AUXV_T] (Elf32_auxv_t): Add typedef.
	[HAVE_ELF64_AUXV_T] (Elf64_auxv_t): Likewise.

diff --git a/gdb/gdbserver/configure.ac b/gdb/gdbserver/configure.ac
index e6e9162..6b98dc0 100644
--- a/gdb/gdbserver/configure.ac
+++ b/gdb/gdbserver/configure.ac
@@ -163,9 +163,10 @@ fi
 
 AC_CHECK_DECLS([strerror, perror, memmem, vasprintf, vsnprintf])
 
-AC_CHECK_TYPES(socklen_t, [], [],
+AC_CHECK_TYPES([socklen_t, Elf32_auxv_t, Elf64_auxv_t], [], [],
 [#include <sys/types.h>
 #include <sys/socket.h>
+#include <elf.h>
 ])
 
 ACX_PKGVERSION([GDB])
diff --git a/gdb/gdbserver/linux-low.c b/gdb/gdbserver/linux-low.c
index d2d4c1d..9aef4db 100644
--- a/gdb/gdbserver/linux-low.c
+++ b/gdb/gdbserver/linux-low.c
@@ -82,6 +82,34 @@
 #endif
 #endif
 
+#ifndef HAVE_ELF32_AUXV_T
+typedef struct
+{
+  uint32_t a_type;		/* Entry type */
+  union
+    {
+      uint32_t a_val;		/* Integer value */
+      /* We use to have pointer elements added here.  We cannot do that,
+	 though, since it does not work when using 32-bit definitions
+	 on 64-bit platforms and vice versa.  */
+    } a_un;
+} Elf32_auxv_t;
+#endif
+
+#ifndef HAVE_ELF64_AUXV_T
+typedef struct
+{
+  uint64_t a_type;		/* Entry type */
+  union
+    {
+      uint64_t a_val;		/* Integer value */
+      /* We use to have pointer elements added here.  We cannot do that,
+	 though, since it does not work when using 32-bit definitions
+	 on 64-bit platforms and vice versa.  */
+    } a_un;
+} Elf64_auxv_t;
+#endif
+
 /* ``all_threads'' is keyed by the LWP ID, which we use as the GDB protocol
    representation of the thread ID.