Found a remappable @Shadow annotation

[Barteks2x]

[00:04:49] [main/ERROR] [mixin]: cubicchunks.mixins.selectable.json:client.optifine.MixinRenderList: Found a remappable @Shadow annotation on preRenderRegion in org.spongepowered.asm.mixin.transformer.MixinInfo$State@49ced9c7
org.spongepowered.asm.mixin.transformer.throwables.InvalidMixinException: Found a remappable @Shadow annotation on preRenderRegion in org.spongepowered.asm.mixin.transformer.MixinInfo$State@49ced9c7
    at org.spongepowered.asm.mixin.transformer.MixinInfo$State.validateRemappable(MixinInfo.java:351) ~[mixin-0.7.5-SNAPSHOT.jar:0.7.5-SNAPSHOT+unknown-b0.git-unknown]
    at org.spongepowered.asm.mixin.transformer.MixinInfo$State.validateRemappables(MixinInfo.java:340) ~[mixin-0.7.5-SNAPSHOT.jar:0.7.5-SNAPSHOT+unknown-b0.git-unknown]
    at org.spongepowered.asm.mixin.transformer.MixinInfo$State.validate(MixinInfo.java:299) ~[mixin-0.7.5-SNAPSHOT.jar:0.7.5-SNAPSHOT+unknown-b0.git-unknown]
    at org.spongepowered.asm.mixin.transformer.MixinInfo.validate(MixinInfo.java:827) ~[mixin-0.7.5-SNAPSHOT.jar:0.7.5-SNAPSHOT+unknown-b0.git-unknown]
    at org.spongepowered.asm.mixin.transformer.MixinConfig.postInitialise(MixinConfig.java:528) [mixin-0.7.5-SNAPSHOT.jar:0.7.5-SNAPSHOT+unknown-b0.git-unknown]
    at org.spongepowered.asm.mixin.transformer.MixinTransformer.prepareConfigs(MixinTransformer.java:675) [mixin-0.7.5-SNAPSHOT.jar:0.7.5-SNAPSHOT+unknown-b0.git-unknown]
    at org.spongepowered.asm.mixin.transformer.MixinTransformer.select(MixinTransformer.java:572) [mixin-0.7.5-SNAPSHOT.jar:0.7.5-SNAPSHOT+unknown-b0.git-unknown]
    at org.spongepowered.asm.mixin.transformer.MixinTransformer.checkSelect(MixinTransformer.java:548) [mixin-0.7.5-SNAPSHOT.jar:0.7.5-SNAPSHOT+unknown-b0.git-unknown]
    at org.spongepowered.asm.mixin.transformer.MixinTransformer.transformClassBytes(MixinTransformer.java:451) [mixin-0.7.5-SNAPSHOT.jar:0.7.5-SNAPSHOT+unknown-b0.git-unknown]
    at org.spongepowered.asm.mixin.transformer.Proxy.transform(Proxy.java:72) [mixin-0.7.5-SNAPSHOT.jar:0.7.5-SNAPSHOT+unknown-b0.git-unknown]
    at net.minecraft.launchwrapper.LaunchClassLoader.runTransformers(LaunchClassLoader.java:279) [launchwrapper-1.12.jar:?]
    at net.minecraft.launchwrapper.LaunchClassLoader.findClass(LaunchClassLoader.java:176) [launchwrapper-1.12.jar:?]
    at java.lang.ClassLoader.loadClass(ClassLoader.java:424) [?:1.8.0_171]
    at java.lang.ClassLoader.loadClass(ClassLoader.java:357) [?:1.8.0_171]
    at java.lang.Class.forName0(Native Method) ~[?:1.8.0_171]
    at java.lang.Class.forName(Class.java:348) [?:1.8.0_171]
    at net.minecraft.launchwrapper.Launch.launch(Launch.java:131) [launchwrapper-1.12.jar:?]
    at net.minecraft.launchwrapper.Launch.main(Launch.java:28) [launchwrapper-1.12.jar:?]
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_171]
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[?:1.8.0_171]
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[?:1.8.0_171]
    at java.lang.reflect.Method.invoke(Method.java:498) ~[?:1.8.0_171]
    at net.minecraftforge.gradle.GradleStartCommon.launch(GradleStartCommon.java:97) [start/:?]
    at GradleStart.main(GradleStart.java:25) [start/:?]

I got this while working on OptiFine E2 support, with the following mixin, in dev environment:

@Mixin({RenderList.class, VboRenderList.class})
public abstract class MixinRenderList extends ChunkRenderContainer {
    @Dynamic @Shadow private void preRenderRegion(int regionX, int regionY, int regionZ) {
        throw new Error();
    }
}

(the actual mixin had much more stuff in it, but this is the smallest one that shows the issue) I know I forgot to set remap = false here, but mixin actually continued anyway, as if nothing happened. And didn't give me much of a clue about what is wrong (and also I read here that those short errors are generally internal errors)

[Mumfrey]

I don't see the problem here? Your mixin has multiple targets and therefore can't contain remappable members.

[Barteks2x]

My point was that mixin seems to ignore the exception, and doesn't give any further diagnostic information. Making the connection between "remappable" and "multiple target" isn't the first thing I would think of when I see that exception.