Hi, I was checking the new synth.tcl

```
-synth_xilinx -vpr -flatten -nosrl
+synth_xilinx -vpr -flatten -abc9 -nosrl -noclkbuf -nodsp

```
I saw that without this change, the following error occurs when using the io_place:

Could not place block $auto$clkbufmap.cc:205:execute$704 (#14); no free locations of type BLK-TL-CLK_BUFG_BOT_R (#4).

What's the flag that prevents this error and why?