From c1c64d86db3b0b57df2c9c055857b871ab84b029 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ond=C5=99ej=20=C4=8Cert=C3=ADk?= <ondrej@certik.us>
Date: Sun, 9 Jul 2023 22:50:28 -0600
Subject: [PATCH] Implement lcompilers_unique_ID global variable

This is initialized to a unique number for each run.
---
 src/bin/lpython.cpp       |  7 +++++++
 src/libasr/asr_scopes.cpp |  2 ++
 src/libasr/utils.h        |  2 ++
 src/libasr/utils2.cpp     | 15 +++++++++++++++
 4 files changed, 26 insertions(+)

diff --git a/src/bin/lpython.cpp b/src/bin/lpython.cpp
index 4eca2b4da3..013c89e04f 100644
--- a/src/bin/lpython.cpp
+++ b/src/bin/lpython.cpp
@@ -44,6 +44,9 @@
     #include <rapidjson/stringbuffer.h>
     #include <rapidjson/writer.h>
 #endif
+
+extern std::string lcompilers_unique_ID;
+
 namespace {
 
 using LCompilers::endswith;
@@ -54,6 +57,7 @@ enum class Backend {
     llvm, cpp, c, x86, wasm, wasm_x86, wasm_x64
 };
 
+
 std::string remove_extension(const std::string& filename) {
     size_t lastdot = filename.find_last_of(".");
     if (lastdot == std::string::npos) return filename;
@@ -1610,6 +1614,9 @@ int main(int argc, char *argv[])
         app.require_subcommand(0, 1);
         CLI11_PARSE(app, argc, argv);
 
+        lcompilers_unique_ID = LCompilers::get_unique_ID();
+
+
         if( compiler_options.fast && compiler_options.enable_bounds_checking ) {
         // ReleaseSafe Mode
         } else if ( compiler_options.fast ) {
diff --git a/src/libasr/asr_scopes.cpp b/src/libasr/asr_scopes.cpp
index acbb50d9c6..ebd3b7c476 100644
--- a/src/libasr/asr_scopes.cpp
+++ b/src/libasr/asr_scopes.cpp
@@ -4,6 +4,8 @@
 #include <libasr/asr_scopes.h>
 #include <libasr/asr_utils.h>
 
+std::string lcompilers_unique_ID;
+
 namespace LCompilers  {
 
 template< typename T >
diff --git a/src/libasr/utils.h b/src/libasr/utils.h
index a0b0c00451..e19e0e3ae4 100644
--- a/src/libasr/utils.h
+++ b/src/libasr/utils.h
@@ -20,6 +20,8 @@ enum Platform {
 std::string pf2s(Platform);
 Platform get_platform();
 
+std::string get_unique_ID();
+
 struct CompilerOptions {
     std::filesystem::path mod_files_dir;
     std::vector<std::filesystem::path> include_dirs;
diff --git a/src/libasr/utils2.cpp b/src/libasr/utils2.cpp
index 62cabe162d..51a2a3c5f4 100644
--- a/src/libasr/utils2.cpp
+++ b/src/libasr/utils2.cpp
@@ -4,6 +4,8 @@
 #endif
 
 #include <fstream>
+#include <filesystem>
+#include <random>
 
 #include <libasr/exception.h>
 #include <libasr/utils.h>
@@ -11,6 +13,19 @@
 
 namespace LCompilers {
 
+std::string get_unique_ID() {
+    static std::random_device dev;
+    static std::mt19937 rng(dev());
+    std::uniform_int_distribution<int> dist(0, 61);
+    const std::string v =
+        "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";
+    std::string res;
+    for (int i = 0; i < 22; i++) {
+        res += v[dist(rng)];
+    }
+    return res;
+}
+
 bool read_file(const std::string &filename, std::string &text)
 {
     std::ifstream ifs(filename.c_str(), std::ios::in | std::ios::binary