Make more compatible with non-linux systems.

* use /usr/bin/env to look for bash
* use pre-defined SHELL variable

Signed-off-by: Yuri Victorovich <yuri@FreeBSD.org>

build_openroad.sh

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 # This script builds the OpenROAD Flow tools locally or in a Docker image.
 
 # Exit on first error, do not allow unbound variables

flow/Makefile

@@ -99,7 +99,7 @@ endif
 
 #-------------------------------------------------------------------------------
 # Proper way to initiate SHELL for make
-SHELL          = /bin/bash
+SHELL          ?= /bin/bash
 .SHELLFLAGS    = -o pipefail -c
 
 #-------------------------------------------------------------------------------

flow/platforms/sky130ram/Makefile

@@ -66,7 +66,8 @@ endif
 # Verbosity
 OPTS += -v
 
-export SHELL := /bin/bash
+SHELL ?= /bin/bash
+export SHELL
 export SHELLOPTS := pipefail
 
 %.ok: configs/%.py | $(OPENRAM_COMPILER) $(SKY130_FD_PR)

flow/test/test_helper.sh

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 
 set -eoux pipefail
 

flow/util/utils.mk

@@ -94,7 +94,7 @@ RUN_ME_SCRIPT = run-me-$(DESIGN_NICKNAME)-$(PLATFORM)-$(FLOW_VARIANT).sh
 
 $(foreach script,$(ISSUE_SCRIPTS),$(script)_issue): %_issue : versions.txt
 	# Creating $(RUN_ME_SCRIPT) script
-	@echo "#!/bin/bash"                             >  $(RUN_ME_SCRIPT)
+	@echo "#!/usr/bin/env bash"                     >  $(RUN_ME_SCRIPT)
 	@echo "source $(VARS_BASENAME).sh"              >> $(RUN_ME_SCRIPT)
 	@echo "openroad -no_init $(SCRIPTS_DIR)/$*.tcl" >> $(RUN_ME_SCRIPT)
 	@chmod +x $(RUN_ME_SCRIPT)