When I change the state of V-Sync (Enabled > Disabled and vice versa) it makes my game crash with following crash report:

Description: Updating screen events

org.lwjgl.opengl.OpenGLException: Stack underflow (1284)
at org.lwjgl.opengl.Util.checkGLError(Util.java:59)
at org.lwjgl.opengl.WindowsContextImplementation.setSwapInterval(WindowsContextImplementation.java:113)
at org.lwjgl.opengl.ContextGL.setSwapInterval(ContextGL.java:232)
at org.lwjgl.opengl.DrawableGL.setSwapInterval(DrawableGL.java:86)
at org.lwjgl.opengl.Display.setSwapInterval(Display.java:1129)
at org.lwjgl.opengl.Display.setVSyncEnabled(Display.java:1142)
at brq.a(SourceFile:560)
at bta.a(SourceFile:89)
at bsw.b(SourceFile:41)
at bvr.a(SourceFile:92)
at bvf.k(SourceFile:405)
at bvr.k(SourceFile:71)
at bvf.p(SourceFile:382)
at bqx.q(SourceFile:1458)
at bqx.ap(SourceFile:866)
at bqx.a(SourceFile:305)
at net.minecraft.client.main.Main.main(SourceFile:120)

A detailed walkthrough of the error, its code path and all known details is as follows:
---------------------------------------------------------------------------------------

– Head –
Stacktrace:
at org.lwjgl.opengl.Util.checkGLError(Util.java:59)
at org.lwjgl.opengl.WindowsContextImplementation.setSwapInterval(WindowsContextImplementation.java:113)
at org.lwjgl.opengl.ContextGL.setSwapInterval(ContextGL.java:232)
at org.lwjgl.opengl.DrawableGL.setSwapInterval(DrawableGL.java:86)
at org.lwjgl.opengl.Display.setSwapInterval(Display.java:1129)
at org.lwjgl.opengl.Display.setVSyncEnabled(Display.java:1142)
at brq.a(SourceFile:560)
at bta.a(SourceFile:89)
at bsw.b(SourceFile:41)
at bvr.a(SourceFile:92)
at bvf.k(SourceFile:405)
at bvr.k(SourceFile:71)
at bvf.p(SourceFile:382)

– Affected screen –
Details:
Screen name: bvr

– Affected level –
Details:
Level name: MpServer
All players: 1 total; [cgh['Hafis_CZ'/261, l='MpServer', x=298,24, y=66,06, z=-534,56]]
Chunk stats: MultiplayerChunkCache: 440, 441
Level seed: 0
Level generator: ID 00 - default, ver 1. Features enabled: false
Level generator options:
Level spawn location: 192,00,64,00,-439,00 - World: (192,64,-439), Chunk: (at 0,4,9 in 12,-28; contains blocks 192,0,-448 to 207,255,-433), Region: (0,-1; contains chunks 0,-32 to 31,-1, blocks 0,0,-512 to 511,255,-1)
Level time: 6773900 game time, 6820687 day time
Level dimension: 0
Level storage version: 0x00000 - Unknown?
Level weather: Rain time: 0 (now: false), thunder time: 0 (now: false)
Level game mode: Game mode: survival (ID 0). Hardcore: false. Cheats: false
Forced entities: 140 total; [cgh['Hafis_CZ'/261, l='MpServer', x=298,24, y=66,06, z=-534,56], acb['Squid'/750625, l='MpServer', x=344,50, y=61,97, z=-477,28], wy['entity.ItemFrame.name'/79, l='MpServer', x=254,50, y=66,50, z=-533,03], wy['entity.ItemFrame.name'/80, l='MpServer', x=251,50, y=66,50, z=-533,03], wy['entity.ItemFrame.name'/81, l='MpServer', x=248,50, y=66,50, z=-533,03], abh['Cow'/84, l='MpServer', x=260,81, y=62,00, z=-592,88], abh['Cow'/85, l='MpServer', x=265,13, y=70,00, z=-595,97], wy['entity.ItemFrame.name'/89, l='MpServer', x=264,97, y=63,50, z=-543,50], wy['entity.ItemFrame.name'/90, l='MpServer', x=266,50, y=66,50, z=-533,03], wy['entity.ItemFrame.name'/91, l='MpServer', x=263,50, y=66,50, z=-533,03], wy['entity.ItemFrame.name'/92, l='MpServer', x=260,50, y=66,50, z=-533,03], wy['entity.ItemFrame.name'/93, l='MpServer', x=257,50, y=66,50, z=-533,03], abd['Bat'/96, l='MpServer', x=274,75, y=52,10, z=-541,25], abd['Bat'/97, l='MpServer', x=274,56, y=52,10, z=-541,25], abd['Bat'/98, l='MpServer', x=276,31, y=53,10, z=-541,25], abd['Bat'/99, l='MpServer', x=279,81, y=54,07, z=-542,48], aby['Sheep'/100, l='MpServer', x=277,19, y=66,00, z=-519,70], aby['Sheep'/101, l='MpServer', x=278,91, y=66,00, z=-519,70], aby['Sheep'/102, l='MpServer', x=278,91, y=66,00, z=-520,94], aby['Sheep'/103, l='MpServer', x=278,91, y=66,00, z=-519,21], aby['Sheep'/104, l='MpServer', x=278,91, y=66,00, z=-520,94], aby['Sheep'/105, l='MpServer', x=276,06, y=66,00, z=-518,69], aby['Sheep'/106, l='MpServer', x=276,06, y=66,00, z=-519,23], aby['Sheep'/107, l='MpServer', x=278,91, y=66,00, z=-520,94], aby['Sheep'/108, l='MpServer', x=276,06, y=66,00, z=-520,94], aby['Sheep'/109, l='MpServer', x=277,81, y=66,00, z=-520,94], aby['Sheep'/110, l='MpServer', x=276,06, y=66,00, z=-518,09], aby['Sheep'/111, l='MpServer', x=276,81, y=66,00, z=-520,94], aby['Sheep'/112, l='MpServer', x=276,06, y=66,00, z=-520,94], aby['Sheep'/113, l='MpServer', x=278,91, y=66,00, z=-518,19], aby['Sheep'/114, l='MpServer', x=277,79, y=66,00, z=-519,22], aby['Sheep'/115, l='MpServer', x=278,91, y=66,00, z=-518,09], aby['Sheep'/116, l='MpServer', x=276,06, y=66,00, z=-519,47], aby['Sheep'/117, l='MpServer', x=277,66, y=66,00, z=-520,94], aby['Sheep'/118, l='MpServer', x=277,91, y=66,00, z=-518,09], aby['Sheep'/119, l='MpServer', x=277,69, y=66,00, z=-520,94], abi['Horse'/120, l='MpServer', x=279,31, y=66,00, z=-516,69], abi['Donkey'/121, l='MpServer', x=281,28, y=66,00, z=-516,47], aby['Sheep'/122, l='MpServer', x=276,06, y=66,00, z=-520,94], abi['Mule'/123, l='MpServer', x=280,22, y=66,00, z=-514,69], aby['Sheep'/124, l='MpServer', x=276,06, y=66,00, z=-520,94], aby['Sheep'/125, l='MpServer', x=278,91, y=66,00, z=-518,09], aby['Sheep'/126, l='MpServer', x=277,69, y=66,00, z=-519,66], aby['Sheep'/127, l='MpServer', x=276,06, y=66,00, z=-519,65], aby['Sheep'/128, l='MpServer', x=276,06, y=66,00, z=-518,09], aby['Sheep'/129, l='MpServer', x=277,39, y=66,00, z=-518,09], aby['Sheep'/130, l='MpServer', x=278,91, y=66,00, z=-519,81], aby['Sheep'/131, l='MpServer', x=277,26, y=66,01, z=-519,23], aby['Sheep'/132, l='MpServer', x=277,20, y=66,00, z=-518,09], abd['Bat'/592013, l='MpServer', x=342,78, y=50,91, z=-598,81], abh['Cow'/133, l='MpServer', x=281,88, y=66,00, z=-519,15], abh['Cow'/134, l='MpServer', x=280,97, y=66,00, z=-519,75], abh['Cow'/135, l='MpServer', x=281,15, y=66,00, z=-518,09], abh['Cow'/136, l='MpServer', x=280,06, y=66,01, z=-519,25], abh['Cow'/137, l='MpServer', x=280,06, y=66,00, z=-520,94], abh['Cow'/138, l='MpServer', x=281,53, y=66,02, z=-520,94], abh['Cow'/139, l='MpServer', x=280,06, y=66,00, z=-520,94], abh['Cow'/140, l='MpServer', x=281,91, y=66,02, z=-520,19], abh['Cow'/141, l='MpServer', x=280,06, y=66,00, z=-519,73], abh['Cow'/142, l='MpServer', x=280,06, y=66,00, z=-518,09], abh['Cow'/143, l='MpServer', x=281,13, y=66,01, z=-520,94], abh['Cow'/144, l='MpServer', x=281,91, y=66,00, z=-519,26], abh['Cow'/145, l='MpServer', x=280,06, y=66,00, z=-520,94], abh['Cow'/146, l='MpServer', x=281,91, y=66,00, z=-518,03], abh['Cow'/147, l='MpServer', x=280,06, y=66,00, z=-518,09], adj['container.minecart'/148, l='MpServer', x=286,50, y=64,06, z=-499,50], adk['entity.MinecartRideable.name'/149, l='MpServer', x=277,50, y=64,06, z=-506,50], adk['entity.MinecartRideable.name'/150, l='MpServer', x=273,50, y=64,06, z=-506,50], acb['Squid'/17302, l='MpServer', x=341,47, y=61,00, z=-480,53], adk['entity.MinecartRideable.name'/151, l='MpServer', x=275,50, y=64,06, z=-504,50], adk['entity.MinecartRideable.name'/152, l='MpServer', x=275,50, y=64,06, z=-508,53], afs['Villager'/153, l='MpServer', x=281,91, y=66,00, z=-499,09], afs['Villager'/154, l='MpServer', x=276,91, y=66,00, z=-499,09], acd['Iron Golem'/155, l='MpServer', x=278,66, y=66,00, z=-498,69], afs['Villager'/156, l='MpServer', x=288,50, y=66,00, z=-490,31], afs['Villager'/157, l='MpServer', x=290,50, y=66,00, z=-494,34], afs['Villager'/158, l='MpServer', x=281,94, y=66,00, z=-495,94], afs['Villager'/159, l='MpServer', x=276,91, y=66,00, z=-498,13], afs['Villager'/160, l='MpServer', x=279,06, y=66,00, z=-497,44], afs['Villager'/161, l='MpServer', x=282,31, y=66,00, z=-493,50], afs['Villager'/162, l='MpServer', x=279,13, y=66,00, z=-495,31], acd['Iron Golem'/163, l='MpServer', x=277,31, y=66,00, z=-490,38], afs['Villager'/164, l='MpServer', x=283,38, y=66,00, z=-491,41], afs['Villager'/165, l='MpServer', x=280,56, y=66,00, z=-492,53], afs['Villager'/166, l='MpServer', x=281,66, y=66,00, z=-493,53], afs['Villager'/167, l='MpServer', x=280,06, y=66,00, z=-491,31], afs['Villager'/168, l='MpServer', x=283,50, y=66,00, z=-490,31], afs['Villager'/169, l='MpServer', x=284,50, y=66,00, z=-490,31], afs['Villager'/170, l='MpServer', x=276,91, y=66,00, z=-493,66], afs['Villager'/171, l='MpServer', x=280,53, y=66,00, z=-490,41], afs['Villager'/172, l='MpServer', x=276,91, y=66,00, z=-489,16], afs['Villager'/173, l='MpServer', x=285,50, y=66,00, z=-489,31], afs['Villager'/174, l='MpServer', x=284,16, y=66,00, z=-493,91], afs['Villager'/175, l='MpServer', x=287,16, y=66,00, z=-493,75], afs['Villager'/176, l='MpServer', x=285,34, y=66,00, z=-493,53], afs['Villager'/177, l='MpServer', x=282,47, y=66,00, z=-491,53], afs['Villager'/178, l='MpServer', x=280,50, y=66,00, z=-487,31], acd['Iron Golem'/179, l='MpServer', x=278,75, y=66,00, z=-492,00], acd['Iron Golem'/180, l='MpServer', x=277,31, y=66,00, z=-495,63], afs['Villager'/181, l='MpServer', x=286,81, y=69,00, z=-494,50], afs['Villager'/182, l='MpServer', x=286,59, y=66,00, z=-491,31], afs['Villager'/183, l='MpServer', x=287,50, y=69,00, z=-491,31], abg['Chicken'/193, l='MpServer', x=300,38, y=66,00, z=-571,66], ada['item.item.egg'/194, l='MpServer', x=295,78, y=70,00, z=-575,69], abd['Bat'/195, l='MpServer', x=303,16, y=42,10, z=-546,53], abd['Bat'/196, l='MpServer', x=300,50, y=42,10, z=-545,25], abd['Bat'/197, l='MpServer', x=303,69, y=42,10, z=-546,75], abh['Cow'/198, l='MpServer', x=295,28, y=66,00, z=-473,56], afs['Villager'/199, l='MpServer', x=290,28, y=66,00, z=-490,69], afs['Villager'/200, l='MpServer', x=293,19, y=66,00, z=-494,34], afs['Villager'/201, l='MpServer', x=288,03, y=66,00, z=-493,50], afs['Villager'/202, l='MpServer', x=288,41, y=66,00, z=-492,66], afs['Villager'/203, l='MpServer', x=288,41, y=66,00, z=-491,31], abh['Cow'/207, l='MpServer', x=306,44, y=70,00, z=-580,25], abd['Bat'/208, l='MpServer', x=306,28, y=58,10, z=-561,63], abd['Bat'/209, l='MpServer', x=304,25, y=43,10, z=-546,75], wy['entity.ItemFrame.name'/210, l='MpServer', x=317,97, y=69,50, z=-544,50], wy['entity.ItemFrame.name'/211, l='MpServer', x=317,97, y=69,50, z=-546,50], wy['entity.ItemFrame.name'/212, l='MpServer', x=316,50, y=69,50, z=-547,97], wy['entity.ItemFrame.name'/213, l='MpServer', x=314,50, y=69,50, z=-547,97], wy['entity.ItemFrame.name'/214, l='MpServer', x=312,50, y=69,50, z=-547,97], wy['entity.ItemFrame.name'/215, l='MpServer', x=304,03, y=69,50, z=-546,50], wy['entity.ItemFrame.name'/216, l='MpServer', x=304,03, y=69,50, z=-544,50], wy['entity.ItemFrame.name'/217, l='MpServer', x=305,50, y=69,50, z=-547,97], wy['entity.ItemFrame.name'/218, l='MpServer', x=307,50, y=69,50, z=-547,97], wy['entity.ItemFrame.name'/219, l='MpServer', x=309,50, y=69,50, z=-547,97], wy['entity.ItemFrame.name'/220, l='MpServer', x=310,50, y=67,50, z=-547,97], wy['entity.ItemFrame.name'/221, l='MpServer', x=310,50, y=68,50, z=-547,97], wy['entity.ItemFrame.name'/222, l='MpServer', x=311,50, y=68,50, z=-547,97], wy['entity.ItemFrame.name'/223, l='MpServer', x=311,50, y=67,50, z=-547,97], wy['entity.ItemFrame.name'/224, l='MpServer', x=304,03, y=69,50, z=-540,50], wy['entity.ItemFrame.name'/225, l='MpServer', x=317,97, y=69,50, z=-540,50], wy['entity.ItemFrame.name'/226, l='MpServer', x=317,97, y=69,50, z=-542,50], wy['entity.ItemFrame.name'/227, l='MpServer', x=304,03, y=69,50, z=-542,50], abh['Cow'/228, l='MpServer', x=317,09, y=66,00, z=-483,13], abh['Cow'/231, l='MpServer', x=334,34, y=63,00, z=-490,72], abh['Cow'/240, l='MpServer', x=347,44, y=66,00, z=-499,47], abd['Bat'/852734, l='MpServer', x=231,93, y=51,11, z=-596,67], abg['Chicken'/246, l='MpServer', x=366,66, y=77,00, z=-594,50], abh['Cow'/250, l='MpServer', x=373,28, y=63,00, z=-467,81]]
Retry entities: 0 total; []
Server brand: vanilla
Server type: Integrated singleplayer server
Stacktrace:
at ccg.a(SourceFile:308)
at bqx.b(SourceFile:2215)
at bqx.a(SourceFile:314)
at net.minecraft.client.main.Main.main(SourceFile:120)

– System Details –
Details:
Minecraft Version: 14w29a
Operating System: Windows 7 (amd64) version 6.1
Java Version: 1.8.0, Oracle Corporation
Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
Memory: 284090616 bytes (270 MB) / 851968000 bytes (812 MB) up to 1908932608 bytes (1820 MB)
JVM Flags: 2 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx2G
IntCache: cache: 1, tcache: 0, allocated: 13, tallocated: 95
Launched Version: 14w29a
LWJGL: 2.9.1
OpenGL: AMD Radeon HD 6670 GL version 4.4.12874 Compatibility Profile Context 14.100.0.0, ATI Technologies Inc.
GL Caps: Using GL 1.3 multitexturing.
Using GL 1.3 texture combiners.
Using framebuffer objects because OpenGL 3.0 is supported and separate blending is supported.
Shaders are available because OpenGL 2.1 is supported.
VBOs are available because OpenGL 1.5 is supported.

Is Modded: Probably not. Jar signature remains and client brand is untouched.
Type: Client (map_client.txt)
Resource Packs: [MinecraftResources++.zip]
Current Language: English (US)
Profiler Position: N/A (disabled)