From b0ed4788858157e271779a7726cccc1149a05407 Mon Sep 17 00:00:00 2001
From: Nathaniel Cesario <nathaniel@lunarg.com>
Date: Tue, 26 Sep 2023 11:50:10 -0600
Subject: [PATCH] Fix race condition identified by TSAN

Guard global variables 'CompileFailed' and 'LinkFailed' in the
StandAlone application with atomics.
---
 StandAlone/StandAlone.cpp | 31 +++++++++++++++++++------------
 1 file changed, 19 insertions(+), 12 deletions(-)

diff --git a/StandAlone/StandAlone.cpp b/StandAlone/StandAlone.cpp
index 8833e38e..b31a6449 100644
--- a/StandAlone/StandAlone.cpp
+++ b/StandAlone/StandAlone.cpp
@@ -51,15 +51,16 @@
 #include "../SPIRV/doc.h"
 #include "../SPIRV/disassemble.h"
 
-#include <cstring>
-#include <cstdlib>
+#include <array>
+#include <atomic>
 #include <cctype>
 #include <cmath>
-#include <array>
+#include <cstdlib>
+#include <cstring>
 #include <map>
 #include <memory>
-#include <thread>
 #include <set>
+#include <thread>
 
 #include "../glslang/OSDependent/osinclude.h"
 
@@ -144,8 +145,9 @@ void FreeFileData(char* data);
 void InfoLogMsg(const char* msg, const char* name, const int num);
 
 // Globally track if any compile or link failure.
-bool CompileFailed = false;
-bool LinkFailed = false;
+std::atomic<int8_t> CompileFailed{0};
+std::atomic<int8_t> LinkFailed{0};
+std::atomic<int8_t> CompileOrLinkFailed{0};
 
 // array of unique places to leave the shader names and infologs for the asynchronous compiles
 std::vector<std::unique_ptr<glslang::TWorkItem>> WorkItems;
@@ -1166,6 +1168,7 @@ void CompileShaders(glslang::TWorklist& worklist)
     if (Options & EOptionDebug)
         Error("cannot generate debug information unless linking to generate code");
 
+    // NOTE: TWorkList::remove is thread-safe
     glslang::TWorkItem* workItem;
     if (Options & EOptionStdin) {
         if (worklist.remove(workItem)) {
@@ -1442,7 +1445,7 @@ void CompileAndLinkShaderUnits(std::vector<ShaderCompUnit> compUnits)
             if (shader->preprocess(GetResources(), defaultVersion, ENoProfile, false, false, messages, &str, includer)) {
                 PutsIfNonEmpty(str.c_str());
             } else {
-                CompileFailed = true;
+                CompileFailed = 1;
             }
             StderrIfNonEmpty(shader->getInfoLog());
             StderrIfNonEmpty(shader->getInfoDebugLog());
@@ -1450,7 +1453,7 @@ void CompileAndLinkShaderUnits(std::vector<ShaderCompUnit> compUnits)
         }
 
         if (! shader->parse(GetResources(), defaultVersion, false, messages, includer))
-            CompileFailed = true;
+            CompileFailed = 1;
 
         if (!compileOnly)
             program.addShader(shader);
@@ -1496,7 +1499,9 @@ void CompileAndLinkShaderUnits(std::vector<ShaderCompUnit> compUnits)
 
     // Dump SPIR-V
     if (Options & EOptionSpv) {
-        if (CompileFailed || LinkFailed)
+        CompileOrLinkFailed.fetch_or(CompileFailed);
+        CompileOrLinkFailed.fetch_or(LinkFailed);
+        if (static_cast<bool>(CompileOrLinkFailed.load()))
             printf("SPIR-V is not generated for failed compile or link\n");
         else {
             std::vector<glslang::TIntermediate*> intermediates;
@@ -1555,7 +1560,9 @@ void CompileAndLinkShaderUnits(std::vector<ShaderCompUnit> compUnits)
         }
     }
 
-    if (depencyFileName && !(CompileFailed || LinkFailed)) {
+    CompileOrLinkFailed.fetch_or(CompileFailed);
+    CompileOrLinkFailed.fetch_or(LinkFailed);
+    if (depencyFileName && !static_cast<bool>(CompileOrLinkFailed.load())) {
         std::set<std::string> includedFiles = includer.getIncludedFiles();
         sources.insert(sources.end(), includedFiles.begin(), includedFiles.end());
 
@@ -1731,9 +1738,9 @@ int singleMain()
         ShFinalize();
     }
 
-    if (CompileFailed)
+    if (CompileFailed.load())
         return EFailCompile;
-    if (LinkFailed)
+    if (LinkFailed.load())
         return EFailLink;
 
     return 0;