From b33bf3f7042464ac4f6e187fc487ee42668fcef7 Mon Sep 17 00:00:00 2001
From: gingerBill <bill@gingerbill.org>
Date: Thu, 26 Aug 2021 22:17:51 +0100
Subject: [PATCH] Correct race condition and incorrect usage of
 `condition_signal` outside of a mutex lock

---
 src/check_stmt.cpp        | 1 +
 src/exact_value.cpp       | 5 +++++
 src/llvm_backend_proc.cpp | 2 ++
 src/main.cpp              | 1 +
 src/thread_pool.cpp       | 2 +-
 5 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/src/check_stmt.cpp b/src/check_stmt.cpp
index 7b039e001..6fc098e6a 100644
--- a/src/check_stmt.cpp
+++ b/src/check_stmt.cpp
@@ -704,6 +704,7 @@ void add_constant_switch_case(CheckerContext *ctx, Map<TypeAndToken> *seen, Oper
 	if (operand.value.kind == ExactValue_Invalid) {
 		return;
 	}
+	
 	HashKey key = hash_exact_value(operand.value);
 	TypeAndToken *found = map_get(seen, key);
 	if (found != nullptr) {
diff --git a/src/exact_value.cpp b/src/exact_value.cpp
index 17b593995..d42f5359e 100644
--- a/src/exact_value.cpp
+++ b/src/exact_value.cpp
@@ -3,6 +3,8 @@
 // TODO(bill): Big numbers
 // IMPORTANT TODO(bill): This needs to be completely fixed!!!!!!!!
 
+gb_global BlockingMutex hash_exact_value_mutex;
+
 struct Ast;
 struct HashKey;
 struct Type;
@@ -62,6 +64,9 @@ struct ExactValue {
 gb_global ExactValue const empty_exact_value = {};
 
 HashKey hash_exact_value(ExactValue v) {
+	mutex_lock(&hash_exact_value_mutex);
+	defer (mutex_unlock(&hash_exact_value_mutex));
+	
 	HashKey empty = {};
 	switch (v.kind) {
 	case ExactValue_Invalid:
diff --git a/src/llvm_backend_proc.cpp b/src/llvm_backend_proc.cpp
index 58f03f4e8..cca1ff196 100644
--- a/src/llvm_backend_proc.cpp
+++ b/src/llvm_backend_proc.cpp
@@ -676,6 +676,8 @@ lbValue lb_emit_call_internal(lbProcedure *p, lbValue value, lbValue return_ptr,
 			for (unsigned i = 0; i < param_count; i++) {
 				LLVMTypeRef param_type = param_types[i];
 				LLVMTypeRef arg_type = LLVMTypeOf(args[i]);
+				// LLVMTypeKind param_kind = LLVMGetTypeKind(param_type);
+				// LLVMTypeKind arg_kind = LLVMGetTypeKind(arg_type);
 				GB_ASSERT_MSG(
 					arg_type == param_type,
 					"Parameter types do not match: %s != %s, argument: %s",
diff --git a/src/main.cpp b/src/main.cpp
index f94b6bd4f..505451141 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -2018,6 +2018,7 @@ int main(int arg_count, char const **arg_ptr) {
 	
 	virtual_memory_init();
 	mutex_init(&fullpath_mutex);
+	mutex_init(&hash_exact_value_mutex);
 
 	init_string_buffer_memory();
 	init_string_interner();
diff --git a/src/thread_pool.cpp b/src/thread_pool.cpp
index a8bc327e5..ed3a065e0 100644
--- a/src/thread_pool.cpp
+++ b/src/thread_pool.cpp
@@ -93,8 +93,8 @@ bool thread_pool_add_task(ThreadPool *pool, WorkerTaskProc *proc, void *data) {
 	thread_pool_queue_push(pool, task);
 	GB_ASSERT(pool->ready >= 0);
 	pool->ready++;
-	mutex_unlock(&pool->mutex);
 	condition_signal(&pool->task_cond);
+	mutex_unlock(&pool->mutex);
 	return true;
 }