Xcode launch app error in Mac 10.9 Mavericks

Question

I using MacOSX 10.9.3 Maverick, xcode 5.1.1 . I try to launch app in simulator, but happen black screen and close xcode. This is notice:

Process:         Xcode [625]
Path:            /Applications/Xcode.app/Contents/MacOS/Xcode
Identifier:      com.apple.dt.Xcode
Version:         5.1.1 (5085)
Build Info:      IDEFrameworks-5085000000000000~10
App Item ID:     497799835
App External ID: 520942841
Code Type:       X86-64 (Native)
Parent Process:  launchd [151]
Responsible:     Xcode [625]
User ID:         501

Date/Time:       2014-05-19 09:43:47.454 +0700
OS Version:      Mac OS X 10.9.3 (13D65)
Report Version:  11
Anonymous UUID:  9C94CD1D-3B3C-6A87-75C0-B9FADF7F71B3


Crashed Thread:  7  Dispatch queue: DBGLLDBLauncher Serial Queue

Exception Type:  EXC_CRASH (SIGABRT)
Exception Codes: 0x0000000000000000, 0x0000000000000000

Application Specific Information:
ProductBuildVersion: 5B1008
Assertion failed: (out_port != 0), function StartDebugserverProcess, file /SourceCache/lldb/lldb-310.2.37/source/Plugins/Process/gdb-remote/GDBRemoteCommunication.cpp, line 720.


Thread 0:: Dispatch queue: com.apple.main-thread
0   libsystem_kernel.dylib          0x00007fff885c9a1a mach_msg_trap + 10
1   libsystem_kernel.dylib          0x00007fff885c8d18 mach_msg + 64
2   com.apple.CoreFoundation        0x00007fff86bdafc5 __CFRunLoopServiceMachPort + 181
3   com.apple.CoreFoundation        0x00007fff86bda5e9 __CFRunLoopRun + 1161
4   com.apple.CoreFoundation        0x00007fff86bd9f25 CFRunLoopRunSpecific + 309
5   com.apple.HIToolbox             0x00007fff8b588a0d RunCurrentEventLoopInMode + 226
...

How to fix it ?

Answer 1

A solution and a workaround to avoid this issue:

Option A (solution)- Ensure your /etc/hosts file contains this entry:

127.0.0.1       localhost

Option B (workaround)- If you really must have 127.0.0.1 mapped differently, eg I happened to be also doing some Facebook API testing that required it set to local.mysite.com, disabling the Xcode debugger:

Product -> Scheme -> Edit Scheme -> Debugger -> None

will also resolve this.

Answer 2

Issue may be caused by another application which removed hosts file, for example MAMP PRO Recreate hosts file

## 
# Host Database 
# 
# localhost is used to configure the loopback interface 
# when the system is booting.  Do not change this entry. 
## 
127.0.0.1       localhost 
255.255.255.255 broadcasthost 
::1             localhost  
fe80::1%lo0     localhost