Properly register error on downstream compiler failure

- The old code was just doing `exit(1)` if glslang or `D3DCompile` failed, which is obviously unacceptable

- The new approach adds the output to the diagnostic buffer (or invokes the callback), and tracks the error count just like any other errors

3 files changed, 44 insertions, 8 deletions

diff --git a/source/slang/compiler.cpp b/source/slang/compiler.cpp
index 7df978707..284bb200a 100644
--- a/source/slang/compiler.cpp
+++ b/source/slang/compiler.cpp
@@ -236,15 +236,14 @@ namespace Slang
             // TODO(tfoley): need a better policy for how we translate diagnostics
             // back into the Slang world (although we should always try to generate
             // HLSL that doesn't produce any diagnostics...)
-            String diagnostics = (char const*) diagnosticsBlob->GetBufferPointer();
-            fprintf(stderr, "%s", diagnostics.begin());
-            OutputDebugStringA(diagnostics.begin());
+            entryPoint->compileRequest->mSink.diagnoseRaw(
+                FAILED(hr) ? Severity::Error : Severity::Warning,
+                (char const*) diagnosticsBlob->GetBufferPointer());
             diagnosticsBlob->Release();
         }
         if (FAILED(hr))
         {
-            // TODO(tfoley): What to do on failure?
-            exit(1);
+            return List<uint8_t>();
         }
         return data;
     }
@@ -376,9 +375,10 @@ namespace Slang
 
         if (err)
         {
-            OutputDebugStringA(diagnosticOutput.Buffer());
-            fprintf(stderr, "%s", diagnosticOutput.Buffer());
-            exit(1);
+            entryPoint->compileRequest->mSink.diagnoseRaw(
+                Severity::Error,
+                diagnosticOutput.begin());
+            return err;
         }
 
         return 0;
diff --git a/source/slang/diagnostics.cpp b/source/slang/diagnostics.cpp
index 0c55a94bd..870e6d172 100644
--- a/source/slang/diagnostics.cpp
+++ b/source/slang/diagnostics.cpp
@@ -194,6 +194,36 @@ void DiagnosticSink::diagnoseImpl(CodePosition const& pos, DiagnosticInfo const&
     }
 }
 
+void DiagnosticSink::diagnoseRaw(
+    Severity    severity,
+    char const* message)
+{
+    if (severity >= Severity::Error)
+    {
+        errorCount++;
+    }
+
+    // Did the client supply a callback for us to use?
+    if( callback )
+    {
+        // If so, pass the error string along to them
+        callback(message, callbackUserData);
+    }
+    else
+    {
+        // If the user doesn't have a callback, then just
+        // collect our diagnostic messages into a buffer
+        outputBuffer.append(message);
+    }
+
+    if (severity >= Severity::Fatal)
+    {
+        // TODO: figure out a better policy for aborting compilation
+        throw InvalidOperationException();
+    }
+}
+
+
 namespace Diagnostics
 {
 #define DIAGNOSTIC(id, severity, name, messageFormat) const DiagnosticInfo name = { id, Severity::severity, messageFormat };
diff --git a/source/slang/diagnostics.h b/source/slang/diagnostics.h
index 8834f1a6e..6957fc763 100644
--- a/source/slang/diagnostics.h
+++ b/source/slang/diagnostics.h
@@ -185,6 +185,12 @@ namespace Slang
         }
 
         void diagnoseImpl(CodePosition const& pos, DiagnosticInfo const& info, int argCount, DiagnosticArg const* const* args);
+
+        // Add a diagnostic with raw text
+        // (used when we get errors from a downstream compiler)
+        void diagnoseRaw(
+            Severity    severity,
+            char const* message);
     };
 
     namespace Diagnostics