For my 1722 build, the gradle.log file is empty (hence why I didn't see any logs). I took a look at 1764, however, and it shows this:
This mapping 'stable_20' was designed for MC 1.8.8! Use at your own peril.This mapping 'stable_20' was designed for MC 1.8.8! Use at your own peril.
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ForgeGradle 2.1-SNAPSHOT-9e8f067
https://github.com/MinecraftForge/ForgeGradle
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Powered by MCP unknown
http://modcoderpack.com
by: Searge, ProfMobius, Fesh0r,
R4wk, ZeuX, IngisKahn, bspkrs
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:deobfCompileDummyTask
:deobfProvidedDummyTask
:eclipseClasspath
:eclipseJdt
:eclipseProject
:getVersionJson
:extractNatives SKIPPED
:extractUserdev UP-TO-DATE
:getAssetIndex UP-TO-DATE
:getAssets
Current status: 542/734 73%
:makeStart
:makeEclipseCleanRunClient
:makeEclipseCleanRunServer
:eclipse
BUILD SUCCESSFUL
Total time: 14.08 secs