Program: 156931
Project: 156931
Buggy source:
private void pipePlugRenderer(RenderBlocks renderblocks,Block block,PipeRenderState state,int x,int y,int z){
  float zFightOffset=1F / 4096F;
  float[][] zeroState=new float[3][2];
  zeroState[0][0]=0.25F + zFightOffset;
  zeroState[0][1]=0.75F - zFightOffset;
  zeroState[1][0]=0.125F;
  zeroState[1][1]=0.25F;
  zeroState[2][0]=0.25F + zFightOffset;
  zeroState[2][1]=0.75F - zFightOffset;
  state.currentTexture=BuildCraftTransport.instance.pipeIconProvider.getIcon(PipeIconProvider.TYPE.PipeStructureCobblestone.ordinal());
  for (  ForgeDirection direction : ForgeDirection.VALID_DIRECTIONS) {
    if (state.plugMatrix.isConnected(direction)) {
      float[][] rotated=deepClone(zeroState);
      transform(rotated,direction);
      block.setBlockBounds(rotated[0][0],rotated[1][0],rotated[2][0],rotated[0][1],rotated[1][1],rotated[2][1]);
      renderblocks.setRenderBoundsFromBlock(block);
      renderblocks.renderStandardBlock(block,x,y,z);
    }
  }
  zeroState[0][0]=0.25F + 0.125F / 2 + zFightOffset;
  zeroState[0][1]=0.75F - 0.125F / 2 + zFightOffset;
  zeroState[1][0]=0.25F;
  zeroState[1][1]=0.25F + 0.125F;
  zeroState[2][0]=0.25F + 0.125F / 2;
  zeroState[2][1]=0.75F - 0.125F / 2;
  state.currentTexture=BuildCraftTransport.instance.pipeIconProvider.getIcon(PipeIconProvider.TYPE.PipeStructureCobblestone.ordinal());
  for (  ForgeDirection direction : ForgeDirection.VALID_DIRECTIONS) {
    if (state.plugMatrix.isConnected(direction)) {
      float[][] rotated=deepClone(zeroState);
      transform(rotated,direction);
      block.setBlockBounds(rotated[0][0],rotated[1][0],rotated[2][0],rotated[0][1],rotated[1][1],rotated[2][1]);
      renderblocks.setRenderBoundsFromBlock(block);
      renderblocks.renderStandardBlock(block,x,y,z);
    }
  }
}

Fixed version (ground truth):
private void pipePlugRenderer(RenderBlocks renderblocks,Block block,PipeRenderState state,int x,int y,int z){
  float zFightOffset=1F / 4096F;
  float[][] zeroState=new float[3][2];
  zeroState[0][0]=0.25F + zFightOffset;
  zeroState[0][1]=0.75F - zFightOffset;
  zeroState[1][0]=0.125F;
  zeroState[1][1]=0.251F;
  zeroState[2][0]=0.25F + zFightOffset;
  zeroState[2][1]=0.75F - zFightOffset;
  state.currentTexture=BuildCraftTransport.instance.pipeIconProvider.getIcon(PipeIconProvider.TYPE.PipeStructureCobblestone.ordinal());
  for (  ForgeDirection direction : ForgeDirection.VALID_DIRECTIONS) {
    if (state.plugMatrix.isConnected(direction)) {
      float[][] rotated=deepClone(zeroState);
      transform(rotated,direction);
      block.setBlockBounds(rotated[0][0],rotated[1][0],rotated[2][0],rotated[0][1],rotated[1][1],rotated[2][1]);
      renderblocks.setRenderBoundsFromBlock(block);
      renderblocks.renderStandardBlock(block,x,y,z);
    }
  }
  zeroState[0][0]=0.25F + 0.125F / 2 + zFightOffset;
  zeroState[0][1]=0.75F - 0.125F / 2 + zFightOffset;
  zeroState[1][0]=0.25F;
  zeroState[1][1]=0.25F + 0.125F;
  zeroState[2][0]=0.25F + 0.125F / 2;
  zeroState[2][1]=0.75F - 0.125F / 2;
  state.currentTexture=BuildCraftTransport.instance.pipeIconProvider.getIcon(PipeIconProvider.TYPE.PipeStructureCobblestone.ordinal());
  for (  ForgeDirection direction : ForgeDirection.VALID_DIRECTIONS) {
    if (state.plugMatrix.isConnected(direction)) {
      float[][] rotated=deepClone(zeroState);
      transform(rotated,direction);
      block.setBlockBounds(rotated[0][0],rotated[1][0],rotated[2][0],rotated[0][1],rotated[1][1],rotated[2][1]);
      renderblocks.setRenderBoundsFromBlock(block);
      renderblocks.renderStandardBlock(block,x,y,z);
    }
  }
}