3 files changed, 34 insertions, 4 deletions
diff --git a/kernel/fstdata.cc b/kernel/fstdata.cc
index fea8ee3c3..b2e574b02 100644
--- a/kernel/fstdata.cc
+++ b/kernel/fstdata.cc
@@ -33,7 +33,7 @@ FstData::FstData(std::string filename) : ctx(nullptr)
 	std::string filename_trim = file_base_name(filename);
 	if (filename_trim.size() > 4 && filename_trim.compare(filename_trim.size()-4, std::string::npos, ".vcd") == 0) {
 		filename_trim.erase(filename_trim.size()-4);
-		tmp_file = stringf("/tmp/converted_%s.fst", filename_trim.c_str());
+		tmp_file = stringf("%s/converted_%s.fst", get_base_tmpdir().c_str(), filename_trim.c_str());
 		std::string cmd = stringf("vcd2fst %s %s", filename.c_str(), tmp_file.c_str());
 		log("Exec: %s\n", cmd.c_str());
 		if (run_command(cmd) != 0)
diff --git a/kernel/yosys.cc b/kernel/yosys.cc
index 4e1a3ca7e..7f395761b 100644
--- a/kernel/yosys.cc
+++ b/kernel/yosys.cc
@@ -376,6 +376,35 @@ int run_command(const std::string &command, std::function<void(const std::string
 }
 #endif
 
+// POSIX defines `TMPDIR` as the pathname of the directory
+// where programs can create temporary files. On most systems,
+// it points to '/tmp'. However, on some systems it can be a different
+// location
+// Source: https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap08.html#tag_08_03
+std::string get_base_tmpdir()
+{
+	// We cache the directory name in a static variable here
+	// for faster calls later
+	static std::string tmpdir;
+
+	if (!tmpdir.empty()) {
+		return tmpdir;
+	}
+
+	char * var = std::getenv("TMPDIR");
+	if (NULL == var) {
+		// if the variable is not set, then use '/tmp'
+		tmpdir.assign("/tmp");
+	} else {
+		tmpdir.assign(var);
+		// We return the directory name without the trailing '/'
+		if (tmpdir.back() == '/') {
+			tmpdir.pop_back();
+		}
+	}
+	return tmpdir;
+}
+
 std::string make_temp_file(std::string template_str)
 {
 #if defined(__wasm)
@@ -384,7 +413,7 @@ std::string make_temp_file(std::string template_str)
 	static size_t index = 0;
 	template_str.replace(pos, 6, stringf("%06zu", index++));
 #elif defined(_WIN32)
-	if (template_str.rfind("/tmp/", 0) == 0) {
+	if (template_str.rfind(get_base_tmpdir() + "/", 0) == 0) {
 #  ifdef __MINGW32__
 		char longpath[MAX_PATH + 1];
 		char shortpath[MAX_PATH + 1];
diff --git a/kernel/yosys.h b/kernel/yosys.h
index 93e7ff23e..448f896d4 100644
--- a/kernel/yosys.h
+++ b/kernel/yosys.h
@@ -278,8 +278,9 @@ bool patmatch(const char *pattern, const char *string);
 #if !defined(YOSYS_DISABLE_SPAWN)
 int run_command(const std::string &command, std::function<void(const std::string&)> process_line = std::function<void(const std::string&)>());
 #endif
-std::string make_temp_file(std::string template_str = "/tmp/yosys_XXXXXX");
-std::string make_temp_dir(std::string template_str = "/tmp/yosys_XXXXXX");
+std::string get_base_tmpdir();
+std::string make_temp_file(std::string template_str = get_base_tmpdir() + "/yosys_XXXXXX");
+std::string make_temp_dir(std::string template_str = get_base_tmpdir() + "/yosys_XXXXXX");
 bool check_file_exists(std::string filename, bool is_exec = false);
 bool is_absolute_path(std::string filename);
 void remove_directory(std::string dirname);