Index: lldb/trunk/include/lldb/Target/Process.h
===================================================================
--- lldb/trunk/include/lldb/Target/Process.h
+++ lldb/trunk/include/lldb/Target/Process.h
@@ -1961,6 +1961,9 @@
     void
     PrintWarningOptimization (const SymbolContext &sc);
 
+    virtual bool
+    GetProcessInfo(ProcessInstanceInfo &info);
+
 public:
     //------------------------------------------------------------------
     /// Get the exit status for a process.
Index: lldb/trunk/packages/Python/lldbsuite/test/functionalities/postmortem/linux-core/TestLinuxCore.py
===================================================================
--- lldb/trunk/packages/Python/lldbsuite/test/functionalities/postmortem/linux-core/TestLinuxCore.py
+++ lldb/trunk/packages/Python/lldbsuite/test/functionalities/postmortem/linux-core/TestLinuxCore.py
@@ -4,29 +4,78 @@
 
 from __future__ import print_function
 
+import shutil
+import struct
+
 import lldb
 from lldbsuite.test.decorators import *
 from lldbsuite.test.lldbtest import *
 from lldbsuite.test import lldbutil
 
 class LinuxCoreTestCase(TestBase):
+    NO_DEBUG_INFO_TESTCASE = True
 
     mydir = TestBase.compute_mydir(__file__)
 
+    _i386_pid   = 32306
+    _x86_64_pid = 32259
+
     @skipIf(bugnumber="llvm.org/pr26947")
-    @no_debug_info_test
     def test_i386(self):
         """Test that lldb can read the process information from an i386 linux core file."""
-        self.do_test("i386", 32306)
+        self.do_test("i386", self._i386_pid)
 
-    @no_debug_info_test
     def test_x86_64(self):
         """Test that lldb can read the process information from an x86_64 linux core file."""
-        self.do_test("x86_64", 32259)
+        self.do_test("x86_64", self._x86_64_pid)
 
-    def do_test(self, arch, pid):
-        target = self.dbg.CreateTarget(arch + ".out")
-        process = target.LoadCore(arch + ".core")
+    def test_same_pid_running(self):
+        """Test that we read the information from the core correctly even if we have a running
+        process with the same PID around"""
+        try:
+            shutil.copyfile("x86_64.out",  "x86_64-pid.out")
+            shutil.copyfile("x86_64.core", "x86_64-pid.core")
+            with open("x86_64-pid.core", "r+b") as f:
+                # These are offsets into the NT_PRSTATUS and NT_PRPSINFO structures in the note
+                # segment of the core file. If you update the file, these offsets may need updating
+                # as well. (Notes can be viewed with readelf --notes.)
+                for pid_offset in [0x1c4, 0x320]:
+                    f.seek(pid_offset)
+                    self.assertEqual(struct.unpack("<I", f.read(4))[0], self._x86_64_pid)
+
+                    # We insert our own pid, and make sure the test still works.
+                    f.seek(pid_offset)
+                    f.write(struct.pack("<I", os.getpid()))
+            self.do_test("x86_64-pid", os.getpid())
+        finally:
+            self.RemoveTempFile("x86_64-pid.out")
+            self.RemoveTempFile("x86_64-pid.core")
+
+    def test_two_cores_same_pid(self):
+        """Test that we handle the situation if we have two core files with the same PID
+        around"""
+        alttarget = self.dbg.CreateTarget("altmain.out")
+        altprocess = alttarget.LoadCore("altmain.core")
+        self.assertTrue(altprocess, PROCESS_IS_VALID)
+        self.assertEqual(altprocess.GetNumThreads(), 1)
+        self.assertEqual(altprocess.GetProcessID(), self._x86_64_pid)
+
+        altframe = altprocess.GetSelectedThread().GetFrameAtIndex(0)
+        self.assertEqual(altframe.GetFunctionName(), "_start")
+        self.assertEqual(altframe.GetLineEntry().GetLine(), line_number("altmain.c", "Frame _start"))
+
+        error = lldb.SBError()
+        F = altprocess.ReadCStringFromMemory(altframe.FindVariable("F").GetValueAsUnsigned(), 256, error)
+        self.assertTrue(error.Success())
+        self.assertEqual(F, "_start")
+
+        # without destroying this process, run the test which opens another core file with the
+        # same pid
+        self.do_test("x86_64", self._x86_64_pid)
+
+    def do_test(self, filename, pid):
+        target = self.dbg.CreateTarget(filename + ".out")
+        process = target.LoadCore(filename + ".core")
         self.assertTrue(process, PROCESS_IS_VALID)
         self.assertEqual(process.GetNumThreads(), 1)
         self.assertEqual(process.GetProcessID(), pid)
Index: lldb/trunk/packages/Python/lldbsuite/test/functionalities/postmortem/linux-core/altmain.c
===================================================================
--- lldb/trunk/packages/Python/lldbsuite/test/functionalities/postmortem/linux-core/altmain.c
+++ lldb/trunk/packages/Python/lldbsuite/test/functionalities/postmortem/linux-core/altmain.c
@@ -0,0 +1,6 @@
+void _start(void)
+{
+    const char *F = "_start";
+    char *boom = (char *)0;
+    *boom = 47; // Frame _start
+}
Index: lldb/trunk/packages/Python/lldbsuite/test/functionalities/postmortem/linux-core/make-core.sh
===================================================================
--- lldb/trunk/packages/Python/lldbsuite/test/functionalities/postmortem/linux-core/make-core.sh
+++ lldb/trunk/packages/Python/lldbsuite/test/functionalities/postmortem/linux-core/make-core.sh
@@ -2,6 +2,14 @@
 
 set -e -x
 
+file=$1
+if [ -z "$file" ]; then
+    cat <<EOF
+Please supply the main source file as the first argument.
+EOF
+    exit 1
+fi
+
 if grep -q '^|' </proc/sys/kernel/core_pattern; then
     cat <<EOF
 Your system uses a crash report tool ($(cat /proc/sys/kernel/core_pattern)). Core files
@@ -21,7 +29,7 @@
 EOF
 fi
 
-${CC:-cc} -nostdlib -static -g $CFLAGS main.c -o a.out
+${CC:-cc} -nostdlib -static -g $CFLAGS "$file" -o a.out
 
 cat <<EOF
 Executable file is in a.out.
Index: lldb/trunk/source/Plugins/DynamicLoader/POSIX-DYLD/DynamicLoaderPOSIXDYLD.cpp
===================================================================
--- lldb/trunk/source/Plugins/DynamicLoader/POSIX-DYLD/DynamicLoaderPOSIXDYLD.cpp
+++ lldb/trunk/source/Plugins/DynamicLoader/POSIX-DYLD/DynamicLoaderPOSIXDYLD.cpp
@@ -656,7 +656,7 @@
     const auto platform_sp = target.GetPlatform ();
 
     ProcessInstanceInfo process_info;
-    if (!platform_sp->GetProcessInfo (m_process->GetID (), process_info))
+    if (!m_process->GetProcessInfo(process_info))
     {
         if (log)
             log->Printf ("DynamicLoaderPOSIXDYLD::%s - failed to get process info for pid %" PRIu64,
Index: lldb/trunk/source/Plugins/Process/elf-core/ProcessElfCore.h
===================================================================
--- lldb/trunk/source/Plugins/Process/elf-core/ProcessElfCore.h
+++ lldb/trunk/source/Plugins/Process/elf-core/ProcessElfCore.h
@@ -111,6 +111,9 @@
     const lldb::DataBufferSP
     GetAuxvData() override;
 
+    bool
+    GetProcessInfo(lldb_private::ProcessInstanceInfo &info) override;
+
 protected:
     void
     Clear ( );
Index: lldb/trunk/source/Plugins/Process/elf-core/ProcessElfCore.cpp
===================================================================
--- lldb/trunk/source/Plugins/Process/elf-core/ProcessElfCore.cpp
+++ lldb/trunk/source/Plugins/Process/elf-core/ProcessElfCore.cpp
@@ -637,3 +637,18 @@
     lldb::DataBufferSP buffer(new lldb_private::DataBufferHeap(start, len));
     return buffer;
 }
+
+bool
+ProcessElfCore::GetProcessInfo(ProcessInstanceInfo &info)
+{
+    info.Clear();
+    info.SetProcessID(GetID());
+    info.SetArchitecture(GetArchitecture());
+    lldb::ModuleSP module_sp = GetTarget().GetExecutableModule();
+    if (module_sp)
+    {
+        const bool add_exe_file_as_first_arg = false;
+        info.SetExecutableFile(GetTarget().GetExecutableModule()->GetFileSpec(), add_exe_file_as_first_arg);
+    }
+    return true;
+}
Index: lldb/trunk/source/Target/Process.cpp
===================================================================
--- lldb/trunk/source/Target/Process.cpp
+++ lldb/trunk/source/Target/Process.cpp
@@ -3422,7 +3422,7 @@
         else if (!process_arch.IsValid())
         {
             ProcessInstanceInfo process_info;
-            platform_sp->GetProcessInfo (GetID(), process_info);
+            GetProcessInfo(process_info);
             const ArchSpec &process_arch = process_info.GetArchitecture();
             if (process_arch.IsValid() && !GetTarget().GetArchitecture().IsExactMatch(process_arch))
             {
@@ -6481,6 +6481,18 @@
     }
 }
 
+bool
+Process::GetProcessInfo(ProcessInstanceInfo &info)
+{
+    info.Clear();
+
+    PlatformSP platform_sp = GetTarget().GetPlatform();
+    if (! platform_sp)
+        return false;
+
+    return platform_sp->GetProcessInfo(GetID(), info);
+}
+
 ThreadCollectionSP
 Process::GetHistoryThreads(lldb::addr_t addr)
 {