diff --git a/kernel/gzip.cc b/kernel/gzip.cc
index f31d535df..d44b03517 100644
--- a/kernel/gzip.cc
+++ b/kernel/gzip.cc
@@ -100,17 +100,17 @@ gzip_istream::ibuf::~ibuf() {
 
 // Takes a successfully opened ifstream. If it's gzipped, returns an istream. Otherwise,
 // returns the original ifstream, rewound to the start.
-std::istream& uncompressed(const std::string filename, std::ios_base::openmode mode) {
-	std::ifstream& f = *new std::ifstream();
-	f.open(filename, mode);
-	if (f.fail())
+std::istream* uncompressed(const std::string filename, std::ios_base::openmode mode) {
+	std::ifstream* f = new std::ifstream();
+	f->open(filename, mode);
+	if (f->fail())
 		return f;
 	// Check for gzip magic
 	unsigned char magic[3];
 	int n = 0;
 	while (n < 3)
 	{
-		int c = f.get();
+		int c = f->get();
 		if (c != EOF) {
 			magic[n] = (unsigned char) c;
 		}
@@ -122,16 +122,16 @@ std::istream& uncompressed(const std::string filename, std::ios_base::openmode m
 		if (magic[2] != 8)
 			log_cmd_error("gzip file `%s' uses unsupported compression type %02x\n",
 				filename.c_str(), unsigned(magic[2]));
-		gzip_istream& s = *new gzip_istream();
-		delete &f;
-		s.open(filename.c_str());
+		gzip_istream* s = new gzip_istream();
+		delete f;
+		s->open(filename.c_str());
 		return s;
 #else
 		log_cmd_error("File `%s' is a gzip file, but Yosys is compiled without zlib.\n", filename.c_str());
 #endif // YOSYS_ENABLE_ZLIB
 	} else {
-		f.clear();
-		f.seekg(0, std::ios::beg);
+		f->clear();
+		f->seekg(0, std::ios::beg);
 		return f;
 	}
 }
diff --git a/kernel/gzip.h b/kernel/gzip.h
index 57eac73c8..aac5340de 100644
--- a/kernel/gzip.h
+++ b/kernel/gzip.h
@@ -71,7 +71,7 @@ private:
 
 #endif // YOSYS_ENABLE_ZLIB
 
-std::istream& uncompressed(const std::string filename, std::ios_base::openmode mode = std::ios_base::in);
+std::istream* uncompressed(const std::string filename, std::ios_base::openmode mode = std::ios_base::in);
 
 YOSYS_NAMESPACE_END
 
diff --git a/kernel/register.cc b/kernel/register.cc
index 040cc6207..7add24601 100644
--- a/kernel/register.cc
+++ b/kernel/register.cc
@@ -470,7 +470,7 @@ void Frontend::extra_args(std::istream *&f, std::string &filename, std::vector<s
 				next_args.insert(next_args.end(), filenames.begin()+1, filenames.end());
 			}
 			yosys_input_files.insert(filename);
-			f = &uncompressed(filename, bin_input ? std::ifstream::binary : std::ifstream::in);
+			f = uncompressed(filename, bin_input ? std::ifstream::binary : std::ifstream::in);
 		}
 		if (f == NULL)
 			log_cmd_error("Can't open input file `%s' for reading: %s\n", filename.c_str(), strerror(errno));
diff --git a/passes/techmap/clockgate.cc b/passes/techmap/clockgate.cc
index 03c436996..8c4aa964d 100644
--- a/passes/techmap/clockgate.cc
+++ b/passes/techmap/clockgate.cc
@@ -309,12 +309,12 @@ struct ClockgatePass : public Pass {
 		if (!liberty_files.empty()) {
 			LibertyMergedCells merged;
 			for (auto path : liberty_files) {
-				std::istream& f = uncompressed(path);
-				if (f.fail())
+				std::istream* f = uncompressed(path);
+				if (f->fail())
 					log_cmd_error("Can't open liberty file `%s': %s\n", path.c_str(), strerror(errno));
-				LibertyParser p(f);
+				LibertyParser p(*f);
 				merged.merge(p);
-				delete &f;
+				delete f;
 			}
 			std::tie(pos_icg_desc, neg_icg_desc) =
 				find_icgs(merged.cells, dont_use_cells);
diff --git a/passes/techmap/dfflibmap.cc b/passes/techmap/dfflibmap.cc
index df2bfa88f..fe4f8aada 100644
--- a/passes/techmap/dfflibmap.cc
+++ b/passes/techmap/dfflibmap.cc
@@ -631,12 +631,12 @@ struct DfflibmapPass : public Pass {
 
 		LibertyMergedCells merged;
 		for (auto path : liberty_files) {
-			std::istream& f = uncompressed(path);
-			if (f.fail())
+			std::istream* f = uncompressed(path);
+			if (f->fail())
 				log_cmd_error("Can't open liberty file `%s': %s\n", path.c_str(), strerror(errno));
-			LibertyParser p(f);
+			LibertyParser p(*f);
 			merged.merge(p);
-			delete &f;
+			delete f;
 		}
 
 		find_cell(merged.cells, ID($_DFF_N_), false, false, false, false, false, false, dont_use_cells);