From 2a08ca9c7003da92c9788b4dcd74290748fab624 Mon Sep 17 00:00:00 2001
From: Jerry Zhao <jerryz123@berkeley.edu>
Date: Fri, 6 Jan 2023 16:48:53 -0800
Subject: [PATCH] Work around old esp-tools

---
 sims/common-sim-flags.mk | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/sims/common-sim-flags.mk b/sims/common-sim-flags.mk
index 7b3deea1..642004f6 100644
--- a/sims/common-sim-flags.mk
+++ b/sims/common-sim-flags.mk
@@ -3,6 +3,17 @@
 #----------------------------------------------------------------------------------------
 SIM_OPT_CXXFLAGS := -O3
 
+# Workaround: esp-isa-sim doesn't install libriscv,
+# so don't link with libriscv if it doesn't exist
+# potentially breaks some configs
+
+ifeq (,$(wildcard $RISCV/lib/libriscv.so))
+$(warning libriscv not found)
+LRISCV=""
+else
+LRISCV="-lriscv"
+endif
+
 SIM_CXXFLAGS = \
 	$(CXXFLAGS) \
 	$(SIM_OPT_CXXFLAGS) \
@@ -18,7 +29,7 @@ SIM_LDFLAGS = \
 	-Wl,-rpath,$(RISCV)/lib \
 	-L$(sim_dir) \
 	-L$(dramsim_dir) \
-	-lriscv \
+	$(LRISCV) \
 	-lfesvr \
 	-ldramsim \
 	$(EXTRA_SIM_LDFLAGS)