gdb/ChangeLog:

2016-01-11  Luis Machado  <lgustavo@codesourcery.com>

	bz 18964

	* mips-tdep.c (mips_gdbarch_init): Sanity check ELF e_machine
	field and bail out if it is not MIPS-compatible.

gdb/testsuite/ChangeLog:

2016-01-11  Luis Machado  <lgustavo@codesourcery.com>

	bz 18964

	* gdb.arch/i376-biarch-core.exp: Handle the core file not being
	recognized.
	Use variables for repeating test names.
---
 gdb/mips-tdep.c                             |  6 ++++++
 gdb/testsuite/gdb.arch/i386-biarch-core.exp | 18 +++++++++++++++---
 2 files changed, 21 insertions(+), 3 deletions(-)

diff --git a/gdb/mips-tdep.c b/gdb/mips-tdep.c
index ca17864..cdfd80e 100644
--- a/gdb/mips-tdep.c
+++ b/gdb/mips-tdep.c
@@ -8208,6 +8208,12 @@ mips_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
   int dspacc;
   int dspctl;
 
+  /* Sanity check the e_machine field.  */
+  if (info.abfd
+      && bfd_get_flavour (info.abfd) == bfd_target_elf_flavour
+      && elf_elfheader (info.abfd)->e_machine != EM_MIPS)
+    return NULL;
+
   /* Fill in the OS dependent register numbers and names.  */
   if (info.osabi == GDB_OSABI_IRIX)
     {
diff --git a/gdb/testsuite/gdb.arch/i386-biarch-core.exp b/gdb/testsuite/gdb.arch/i386-biarch-core.exp
index 607b947..a4c0541 100644
--- a/gdb/testsuite/gdb.arch/i386-biarch-core.exp
+++ b/gdb/testsuite/gdb.arch/i386-biarch-core.exp
@@ -28,13 +28,14 @@ gdb_start
 gdb_reinitialize_dir $srcdir/$subdir
 
 set test "complete set gnutarget"
+set text_test ".text is readable"
 gdb_test_multiple "complete set gnutarget " $test {
     -re "set gnutarget elf64-little\r\n(.*\r\n)?$gdb_prompt $" {
 	pass $test
     }
     -re "\r\n$gdb_prompt $" {
 	pass $test
-	untested ".text is readable"
+	untested $text_test
 	return
     }
 }
@@ -62,8 +63,19 @@ if {$corestat(size) != 102400} {
 # objcopy as it corrupts the core file beyond all recognition.
 # The output therefore does not matter much, just we should not get GDB
 # internal error.
-gdb_test "core-file ${corefile}" ".*" "core-file"
+set test "core-file"
+gdb_test_multiple "core-file ${corefile}" $test {
+    -re ".* no core file handler recognizes format\r\n$gdb_prompt $" {
+	# Make sure we handle cases where the core file isn't even properly
+	# loaded due to architecture incompatibilities.
+	untested $text_test
+	return
+    }
+    -re "\r\n$gdb_prompt $" {
+	pass $test
+    }
+}
 
 # Test if at least the core file segments memory has been loaded.
 # https://bugzilla.redhat.com/show_bug.cgi?id=457187
-gdb_test "x/bx $address" "\r\n\[ \t\]*$address:\[ \t\]*0xf4\[ \t\]*" ".text is readable"
+gdb_test "x/bx $address" "\r\n\[ \t\]*$address:\[ \t\]*0xf4\[ \t\]*" $text_test
-- 
1.9.1