LEC: default on for ORFS test scripts

If LEC fails, then the user should report a github issue
and go about his business.

If LEC doesn't fail on the final netlist, then other than
causing friction during development, LEC during development
isn't an issue

Signed-off-by: Øyvind Harboe <oyvind.harboe@zylin.com>

Author: oharboe

docs/user/FlowVariables.md

@@ -162,7 +162,7 @@ configuration file.
 | <a name="KLAYOUT_TECH_FILE"></a>KLAYOUT_TECH_FILE| A mapping from LEF/DEF to GDS using the KLayout tool.| |
 | <a name="LATCH_MAP_FILE"></a>LATCH_MAP_FILE| Optional mapping file supplied to Yosys to map latches| |
 | <a name="LAYER_PARASITICS_FILE"></a>LAYER_PARASITICS_FILE| Path to per layer parasitics file. Defaults to $(PLATFORM_DIR)/setRC.tcl.| |
-| <a name="LEC_CHECK"></a>LEC_CHECK| Perform a formal equivalence check between before and after netlists.| 1|
+| <a name="LEC_CHECK"></a>LEC_CHECK| Perform a formal equivalence check between before and after netlists. If this fails, report an issue to OpenROAD.| 0|
 | <a name="LIB_FILES"></a>LIB_FILES| A Liberty file of the standard cell library with PVT characterization, input and output characteristics, timing and power definitions for each cell.| |
 | <a name="MACRO_BLOCKAGE_HALO"></a>MACRO_BLOCKAGE_HALO| Distance beyond the edges of a macro that will also be covered by the blockage generated for that macro. Note that the default macro blockage halo comes from the largest of the specified MACRO_PLACE_HALO x or y values. This variable overrides that calculation.| |
 | <a name="MACRO_EXTENSION"></a>MACRO_EXTENSION| Sets the number of GCells added to the blockages boundaries from macros.| |

flow/scripts/variables.yaml

@@ -1298,7 +1298,9 @@ WRITE_ODB_AND_SDC_EACH_STAGE:
 LEC_CHECK:
   description: >
     Perform a formal equivalence check between before and after netlists.
-  default: 1
+
+    If this fails, report an issue to OpenROAD.
+  default: 0
   stages:
     - cts
 REMOVE_CELLS_FOR_LEC:

flow/settings.mk

@@ -0,0 +1 @@
+export LEC_CHECK ?= 1