diff --git a/Makefile b/Makefile
index 1a021efe2..bc102f5e4 100644
--- a/Makefile
+++ b/Makefile
@@ -176,7 +176,7 @@ ifeq ($(OS), Haiku)
 CXXFLAGS += -D_DEFAULT_SOURCE
 endif
 
-YOSYS_VER := 0.55+46
+YOSYS_VER := 0.55+112
 YOSYS_MAJOR := $(shell echo $(YOSYS_VER) | cut -d'.' -f1)
 YOSYS_MINOR := $(shell echo $(YOSYS_VER) | cut -d'.' -f2)
 YOSYS_COMMIT := $(shell echo $(YOSYS_VER) | cut -d'.' -f3)
diff --git a/frontends/ast/simplify.cc b/frontends/ast/simplify.cc
index 05621d857..4d8c57ced 100644
--- a/frontends/ast/simplify.cc
+++ b/frontends/ast/simplify.cc
@@ -1759,7 +1759,7 @@ bool AstNode::simplify(bool const_fold, int stage, int width_hint, bool sign_hin
 			break;
 		if (type == AST_GENBLOCK)
 			break;
-		if (type == AST_CELLARRAY && children[i]->type == AST_CELL)
+		if (type == AST_CELLARRAY && (children[i]->type == AST_CELL || children[i]->type == AST_PRIMITIVE))
 			continue;
 		if (type == AST_BLOCK && !str.empty())
 			break;
@@ -2752,6 +2752,7 @@ bool AstNode::simplify(bool const_fold, int stage, int width_hint, bool sign_hin
 			if (new_cell->type == AST_PRIMITIVE) {
 				input_error("Cell arrays of primitives are currently not supported.\n");
 			} else {
+				this->dumpAst(NULL, "    ");
 				log_assert(new_cell->children.at(0)->type == AST_CELLTYPE);
 				new_cell->children.at(0)->str = stringf("$array:%d:%d:%s", i, num, new_cell->children.at(0)->str.c_str());
 			}
diff --git a/tests/verilog/bug4785.ys b/tests/verilog/bug4785.ys
new file mode 100644
index 000000000..174765983
--- /dev/null
+++ b/tests/verilog/bug4785.ys
@@ -0,0 +1,9 @@
+logger -expect error "Cell arrays of primitives are currently not supported" 1
+read_verilog <<EOT
+module test(in1, in2, out1);
+  input in1, in2;
+  output out1;
+
+  nand  #2 t_nand[0:7](out1, in1, in2);
+endmodule
+EOT