Im using the java installer.:

 

Linux aditya-desktop 3.12-1-686-pae #1 SMP Debian 3.12.9-1 (2014-02-01) i686 GNU/Linux

Forge installes fine

aditya@aditya-desktop  ~/Desktop  java -jar forge-1.7.2-10.12.0.1024-installer.jar
Considering library net.minecraftforge:forge:1.7.2-10.12.0.1024
Considering library net.minecraft:launchwrapper:1.9
Considering library org.ow2.asm:asm-all:4.1
Considering library org.scala-lang:scala-library:2.10.2
Checking "/home/aditya/.minecraft/libraries/org/scala-lang/scala-library/2.10.2/scala-library-2.10.2.jar" internal checksums
    checksums.sha1 validated successfully
    Jar contents validated successfully
Considering library org.scala-lang:scala-compiler:2.10.2
Checking "/home/aditya/.minecraft/libraries/org/scala-lang/scala-compiler/2.10.2/scala-compiler-2.10.2.jar" internal checksums
    checksums.sha1 validated successfully
    Jar contents validated successfully
Considering library java3d:vecmath:1.3.1
Considering library net.sf.trove4j:trove4j:3.0.3
Considering library com.ibm.icu:icu4j-core-mojang:51.2
Considering library net.sf.jopt-simple:jopt-simple:4.5
Considering library lzma:lzma:0.0.1
Considering library com.paulscode:codecjorbis:20101023
Considering library com.paulscode:codecwav:20101023
Considering library com.paulscode:libraryjavasound:20101123
Considering library com.paulscode:librarylwjglopenal:20100824
Considering library com.paulscode:soundsystem:20120107
Considering library io.netty:netty-all:4.0.10.Final
Considering library com.google.guava:guava:15.0
Considering library org.apache.commons:commons-lang3:3.1
Considering library commons-io:commons-io:2.4
Considering library net.java.jinput:jinput:2.0.5
Considering library net.java.jutils:jutils:1.0.0
Considering library com.google.code.gson:gson:2.2.4
Considering library com.mojang:authlib:1.3
Considering library org.apache.logging.log4j:log4j-api:2.0-beta9
Considering library org.apache.logging.log4j:log4j-core:2.0-beta9
Considering library org.lwjgl.lwjgl:lwjgl:2.9.0
Considering library org.lwjgl.lwjgl:lwjgl_util:2.9.0
Considering library org.lwjgl.lwjgl:lwjgl-platform:2.9.0
Considering library org.lwjgl.lwjgl:lwjgl:2.9.1-nightly-20131017
Considering library org.lwjgl.lwjgl:lwjgl_util:2.9.1-nightly-20131017
Considering library org.lwjgl.lwjgl:lwjgl-platform:2.9.1-nightly-20131017
Considering library net.java.jinput:jinput-platform:2.0.5

 

And when I launch the log says:

 

[15:18:24 INFO]: Launching game
[15:18:24 INFO]: Looking for old natives & assets to clean up...
[15:18:24 INFO]: Unpacking natives to /home/aditya/.minecraft/versions/1.7.2-Forge10.12.0.1024/1.7.2-Forge10.12.0.1024-natives-1776144415899
[15:18:24 INFO]: Reconstructing virtual assets folder at /home/aditya/.minecraft/assets/virtual/legacy
[15:18:24 INFO]: Launching in /home/aditya/.minecraft
[15:18:24 INFO]: Half command: /usr/lib/jvm/java-7-oracle/jre/bin/java -Xmx512M -Djava.library.path=/home/aditya/.minecraft/versions/1.7.2-Forge10.12.0.1024/1.7.2-Forge10.12.0.1024-natives-1776144415899 -cp /home/aditya/.minecraft/libraries/net/minecraftforge/forge/1.7.2-10.12.0.1024/forge-1.7.2-10.12.0.1024.jar:/home/aditya/.minecraft/libraries/net/minecraft/launchwrapper/1.9/launchwrapper-1.9.jar:/home/aditya/.minecraft/libraries/org/ow2/asm/asm-all/4.1/asm-all-4.1.jar:/home/aditya/.minecraft/libraries/org/scala-lang/scala-library/2.10.2/scala-library-2.10.2.jar:/home/aditya/.minecraft/libraries/org/scala-lang/scala-compiler/2.10.2/scala-compiler-2.10.2.jar:/home/aditya/.minecraft/libraries/java3d/vecmath/1.3.1/vecmath-1.3.1.jar:/home/aditya/.minecraft/libraries/net/sf/trove4j/trove4j/3.0.3/trove4j-3.0.3.jar:/home/aditya/.minecraft/libraries/com/ibm/icu/icu4j-core-mojang/51.2/icu4j-core-mojang-51.2.jar:/home/aditya/.minecraft/libraries/net/sf/jopt-simple/jopt-simple/4.5/jopt-simple-4.5.jar:/home/aditya/.minecraft/libraries/lzma/lzma/0.0.1/lzma-0.0.1.jar:/home/aditya/.minecraft/libraries/com/paulscode/codecjorbis/20101023/codecjorbis-20101023.jar:/home/aditya/.minecraft/libraries/com/paulscode/codecwav/20101023/codecwav-20101023.jar:/home/aditya/.minecraft/libraries/com/paulscode/libraryjavasound/20101123/libraryjavasound-20101123.jar:/home/aditya/.minecraft/libraries/com/paulscode/librarylwjglopenal/20100824/librarylwjglopenal-20100824.jar:/home/aditya/.minecraft/libraries/com/paulscode/soundsystem/20120107/soundsystem-20120107.jar:/home/aditya/.minecraft/libraries/io/netty/netty-all/4.0.10.Final/netty-all-4.0.10.Final.jar:/home/aditya/.minecraft/libraries/com/google/guava/guava/15.0/guava-15.0.jar:/home/aditya/.minecraft/libraries/org/apache/commons/commons-lang3/3.1/commons-lang3-3.1.jar:/home/aditya/.minecraft/libraries/commons-io/commons-io/2.4/commons-io-2.4.jar:/home/aditya/.minecraft/libraries/net/java/jinput/jinput/2.0.5/jinput-2.0.5.jar:/home/aditya/.minecraft/libraries/net/java/jutils/jutils/1.0.0/jutils-1.0.0.jar:/home/aditya/.minecraft/libraries/com/google/code/gson/gson/2.2.4/gson-2.2.4.jar:/home/aditya/.minecraft/libraries/com/mojang/authlib/1.3/authlib-1.3.jar:/home/aditya/.minecraft/libraries/org/apache/logging/log4j/log4j-api/2.0-beta9/log4j-api-2.0-beta9.jar:/home/aditya/.minecraft/libraries/org/apache/logging/log4j/log4j-core/2.0-beta9/log4j-core-2.0-beta9.jar:/home/aditya/.minecraft/libraries/org/lwjgl/lwjgl/lwjgl/2.9.0/lwjgl-2.9.0.jar:/home/aditya/.minecraft/libraries/org/lwjgl/lwjgl/lwjgl_util/2.9.0/lwjgl_util-2.9.0.jar:/home/aditya/.minecraft/versions/1.7.2-Forge10.12.0.1024/1.7.2-Forge10.12.0.1024.jar net.minecraft.launchwrapper.Launch
[15:18:25 INFO]: Client> [15:18:25] [main/INFO] [LaunchWrapper]: Loading tweak class name cpw.mods.fml.common.launcher.FMLTweaker
[15:18:25 INFO]: Client> [15:18:25] [main/INFO] [LaunchWrapper]: Using primary tweak class name cpw.mods.fml.common.launcher.FMLTweaker
[15:18:25 INFO]: Client> [15:18:25] [main/INFO] [LaunchWrapper]: Calling tweak class cpw.mods.fml.common.launcher.FMLTweaker
[15:18:25 INFO]: Client> [15:18:25] [main/INFO] [FML]: Forge Mod Loader version 7.2.116.1024 for Minecraft 1.7.2 loading
[15:18:25 INFO]: Client> [15:18:25] [main/INFO] [FML]: Java is Java HotSpot(TM) Server VM, version 1.7.0_25, running on Linux:i386:3.12-1-686-pae, installed at /usr/lib/jvm/java-7-oracle/jre
[15:18:25 INFO]: Client> [15:18:25] [main/INFO] [LaunchWrapper]: Loading tweak class name cpw.mods.fml.common.launcher.FMLInjectionAndSortingTweaker
[15:18:25 INFO]: Client> [15:18:25] [main/INFO] [LaunchWrapper]: Loading tweak class name cpw.mods.fml.common.launcher.FMLDeobfTweaker
[15:18:25 INFO]: Client> [15:18:25] [main/INFO] [LaunchWrapper]: Calling tweak class cpw.mods.fml.common.launcher.FMLInjectionAndSortingTweaker
[15:18:25 INFO]: Client> [15:18:25] [main/INFO] [LaunchWrapper]: Calling tweak class cpw.mods.fml.common.launcher.FMLInjectionAndSortingTweaker
[15:18:25 INFO]: Client> [15:18:25] [main/INFO] [LaunchWrapper]: Calling tweak class cpw.mods.fml.relauncher.CoreModManager$FMLPluginWrapper
[15:18:26 INFO]: Client> [15:18:26] [main/ERROR] [LaunchWrapper]: Unable to launch
[15:18:26 INFO]: Client> java.lang.RuntimeException: java.lang.NullPointerException
[15:18:26 INFO]: Client> 	at cpw.mods.fml.relauncher.CoreModManager$FMLPluginWrapper.injectIntoClassLoader(CoreModManager.java:130) ~[forge-1.7.2-10.12.0.1024.jar:?]
[15:18:26 INFO]: Client> 	at net.minecraft.launchwrapper.Launch.launch(Launch.java:114) [launchwrapper-1.9.jar:?]
[15:18:26 INFO]: Client> 	at net.minecraft.launchwrapper.Launch.main(Launch.java:28) [launchwrapper-1.9.jar:?]
[15:18:26 INFO]: Client> Caused by: java.lang.NullPointerException
[15:18:26 INFO]: Client> 	at com.google.common.base.Preconditions.checkNotNull(Preconditions.java:192) ~[guava-15.0.jar:?]
[15:18:26 INFO]: Client> 	at com.google.common.hash.AbstractByteHasher.putBytes(AbstractByteHasher.java:69) ~[guava-15.0.jar:?]
[15:18:26 INFO]: Client> 	at com.google.common.hash.AbstractStreamingHashFunction.hashBytes(AbstractStreamingHashFunction.java:65) ~[guava-15.0.jar:?]
[15:18:26 INFO]: Client> 	at cpw.mods.fml.common.patcher.ClassPatchManager.applyPatch(ClassPatchManager.java:95) ~[forge-1.7.2-10.12.0.1024.jar:?]
[15:18:26 INFO]: Client> 	at cpw.mods.fml.common.patcher.ClassPatchManager.getPatchedResource(ClassPatchManager.java:60) ~[forge-1.7.2-10.12.0.1024.jar:?]
[15:18:26 INFO]: Client> 	at cpw.mods.fml.common.asm.transformers.deobf.FMLDeobfuscatingRemapper.getFieldType(FMLDeobfuscatingRemapper.java:210) ~[forge-1.7.2-10.12.0.1024.jar:?]
[15:18:26 INFO]: Client> 	at cpw.mods.fml.common.asm.transformers.deobf.FMLDeobfuscatingRemapper.parseField(FMLDeobfuscatingRemapper.java:187) ~[forge-1.7.2-10.12.0.1024.jar:?]
[15:18:26 INFO]: Client> 	at cpw.mods.fml.common.asm.transformers.deobf.FMLDeobfuscatingRemapper.setup(FMLDeobfuscatingRemapper.java:148) ~[forge-1.7.2-10.12.0.1024.jar:?]
[15:18:26 INFO]: Client> 	at cpw.mods.fml.common.asm.FMLSanityChecker.injectData(FMLSanityChecker.java:179) ~[forge-1.7.2-10.12.0.1024.jar:?]
[15:18:26 INFO]: Client> 	at cpw.mods.fml.relauncher.CoreModManager$FMLPluginWrapper.injectIntoClassLoader(CoreModManager.java:125) ~[forge-1.7.2-10.12.0.1024.jar:?]
[15:18:26 INFO]: Client> 	... 2 more
[15:18:26 INFO]: Game ended with no troubles detected (exit code 0)
[15:18:26 INFO]: Deleting /home/aditya/.minecraft/versions/1.7.2-Forge10.12.0.1024/1.7.2-Forge10.12.0.1024-natives-1776144415899
[15:18:26 INFO]: Following visibility rule and exiting launcher as the game has ended

 

 

I don't see any logs in my .minecraft dir. Infact, there is not ForgeModloader folder at all (although there is an empty mods folder)

 

Its not 'ForgeModLoader' folder, it's just the 'logs' folder, Vanilla minecraft puts logs in there as well.

However, this issue is caused by it not being able to find the base of a class that it trying to patch.

More information should be obtainable in the log from the logs folder.

However as a guess on the fix, go into the versions folder delete both the vanilla 1.7.2, and the forge folder.

Run vanilla 1.7.2 and then reinstall Forge. To make sure that you have a vanila 1.7.2 base jar.

Thanks, it worked after flushing my libs folder