Fixes, tweaks and improvements for Linux support

Source/Engine/Platform/Linux/LinuxPlatform.cpp

@@ -2140,7 +2140,12 @@ int32 LinuxPlatform::RunProcess(const StringView& cmdLine, const StringView& wor
 void* LinuxPlatform::LoadLibrary(const Char* filename)
 {
     const StringAsANSI<> filenameANSI(filename);
-	return dlopen(filenameANSI.Get(), RTLD_LAZY);
+    void* result = dlopen(filenameANSI.Get(), RTLD_LAZY | RTLD_LOCAL);
+    if (!result)
+    {
+        LOG(Error, "Failed to load {0} because {1}", filename, String(dlerror()));
+    }
+    return result;
 }
 
 void LinuxPlatform::FreeLibrary(void* handle)

Source/Tools/Flax.Build/Platforms/Linux/LinuxToolchain.cs

@@ -43,8 +43,22 @@ namespace Flax.Build.Platforms
         {
             base.SetupCompileCppFilesArgs(graph, options, args, outputPath);
 
+            // Hide all symbols by default
+            args.Add("-fvisibility-inlines-hidden");
+            args.Add("-fvisibility-ms-compat");
+
             args.Add(string.Format("-target {0}", ArchitectureName));
             args.Add(string.Format("--sysroot=\"{0}\"", ToolsetRoot.Replace('\\', '/')));
+
+            if (Architecture == TargetArchitecture.x64)
+            {
+                args.Add("-mssse3");
+            }
+
+            if (options.Target.OutputType == TargetOutputType.Library)
+            {
+                args.Add("-fPIC");
+            }
         }
 
         /// <inheritdoc />
@@ -53,8 +67,6 @@ namespace Flax.Build.Platforms
             base.SetupLinkFilesArgs(graph, options, args, outputFilePath);
 
             args.Add("-Wl,-rpath,\"\\$ORIGIN\"");
-
-            // Speed up build
             //args.Add("-Wl,--as-needed");
             args.Add("-Wl,--hash-style=gnu");
             //args.Add("-Wl,--build-id");
@@ -62,7 +74,7 @@ namespace Flax.Build.Platforms
             if (options.LinkEnv.Output == LinkerOutput.SharedLibrary)
             {
                 args.Add("-shared");
-                args.Add(string.Format("-soname=\"{0}\"", Path.GetFileNameWithoutExtension(outputFilePath)));
+                args.Add(string.Format("-Wl,-soname=\"{0}\"", Path.GetFileNameWithoutExtension(outputFilePath)));
             }
 
             args.Add(string.Format("-target {0}", ArchitectureName));

Source/Tools/Flax.Build/Platforms/Unix/UnixToolchain.cs

@@ -255,12 +255,8 @@ namespace Flax.Build.Platforms
             var commonArgs = new List<string>();
             SetupCompileCppFilesArgs(graph, options, commonArgs, outputPath);
             {
-                // Don't link, only compile code
                 commonArgs.Add("-c");
-
                 commonArgs.Add("-pipe");
-
-                // C++ compile flags
                 commonArgs.Add("-x");
                 commonArgs.Add("c++");
                 commonArgs.Add("-std=c++14");
@@ -280,25 +276,6 @@ namespace Flax.Build.Platforms
                 if (compileEnvironment.TreatWarningsAsErrors)
                     commonArgs.Add("-Wall -Werror");
 
-                /*
-                if (ShouldUseLibcxx(CompileEnvironment.Architecture))
-                {
-                    commonArgs.Add("-nostdinc++");
-                    commonArgs.Add("-I" + "ThirdParty/Linux/LibCxx/include/");
-                    commonArgs.Add("-I" + "ThirdParty/Linux/LibCxx/include/c++/v1");
-                }
-                 */
-                /*
-               if (Options.HasFlag(LinuxToolChainOptions.EnableAddressSanitizer))
-                   commonArgs.Add("-fsanitize=address");
-
-               if (Options.HasFlag(LinuxToolChainOptions.EnableThreadSanitizer))
-                   commonArgs.Add("-fsanitize=thread");
-
-               if (Options.HasFlag(LinuxToolChainOptions.EnableUndefinedBehaviorSanitizer))
-                   commonArgs.Add("-fsanitize=undefined");
-               */
-
                 // TODO: compileEnvironment.IntrinsicFunctions
                 // TODO: compileEnvironment.FunctionLevelLinking
                 // TODO: compileEnvironment.FavorSizeOrSpeed
@@ -469,12 +446,18 @@ namespace Flax.Build.Platforms
             foreach (var library in linkEnvironment.InputLibraries)
             {
                 var dir = Path.GetDirectoryName(library);
+                var ext = Path.GetExtension(library);
                 if (string.IsNullOrEmpty(dir))
                 {
                     args.Add(string.Format("\"-l{0}\"", library));
                 }
-                else if (library.EndsWith(".so"))
+                else if (string.IsNullOrEmpty(ext))
                 {
+                    // Skip executable
+                }
+                else if (ext == ".so")
+                {
+                    // Link against dynamic library
                     task.PrerequisiteFiles.Add(library);
                     libraryPaths.Add(dir);
                     args.Add(string.Format("\"-l{0}\"", GetLibName(library)));
@@ -488,12 +471,18 @@ namespace Flax.Build.Platforms
             foreach (var library in options.Libraries)
             {
                 var dir = Path.GetDirectoryName(library);
+                var ext = Path.GetExtension(library);
                 if (string.IsNullOrEmpty(dir))
                 {
                     args.Add(string.Format("\"-l{0}\"", library));
                 }
-                else if (library.EndsWith(".so"))
+                else if (string.IsNullOrEmpty(ext))
                 {
+                    // Skip executable
+                }
+                else if (ext == ".so")
+                {
+                    // Link against dynamic library
                     task.PrerequisiteFiles.Add(library);
                     libraryPaths.Add(dir);
                     args.Add(string.Format("\"-l{0}\"", GetLibName(library)));