[ORC] Add a C API function to set the ExecutionSession error reporter.

include/llvm-c/Orc.h

@@ -46,9 +46,14 @@ typedef struct LLVMOrcOpaqueExecutionSession *LLVMOrcExecutionSessionRef;
 /**
  * A reference to an orc::SymbolStringPool table entry.
  */
-typedef struct LLVMOrcQuaqueSymbolStringPoolEntryPtr
+typedef struct LLVMOrcOpaqueSymbolStringPoolEntry
     *LLVMOrcSymbolStringPoolEntryRef;
 
+/**
+ * Error reporter function.
+ */
+typedef void (*LLVMOrcErrorReporterFunction)(void *Ctx, LLVMErrorRef Err);
+
 /**
  * A reference to an orc::JITDylib instance.
  */
@@ -92,6 +97,19 @@ typedef struct LLVMOrcOpaqueLLJITBuilder *LLVMOrcLLJITBuilderRef;
  */
 typedef struct LLVMOrcOpaqueLLJIT *LLVMOrcLLJITRef;
 
+/**
+ * Attach a custom error reporter function to the ExecutionSession.
+ *
+ * The error reporter will be called to deliver failure notices that can not be
+ * directly reported to a caller. For example, failure to resolve symbols in
+ * the JIT linker is typically reported via the error reporter (callers
+ * requesting definitions from the JIT will typically be delivered a
+ * FailureToMaterialize error instead).
+ */
+void LLVMOrcExecutionSessionSetErrorReporter(
+    LLVMOrcExecutionSessionRef ES, LLVMOrcErrorReporterFunction ReportError,
+    void *Ctx);
+
 /**
  * Intern a string in the ExecutionSession's SymbolStringPool and return a
  * reference to it. This increments the ref-count of the pool entry, and the

lib/ExecutionEngine/Orc/OrcV2CBindings.cpp

@@ -58,6 +58,13 @@ DEFINE_SIMPLE_CONVERSION_FUNCTIONS(LLJIT, LLVMOrcLLJITRef)
 
 DEFINE_SIMPLE_CONVERSION_FUNCTIONS(TargetMachine, LLVMTargetMachineRef)
 
+void LLVMOrcExecutionSessionSetErrorReporter(
+    LLVMOrcExecutionSessionRef ES, LLVMOrcErrorReporterFunction ReportError,
+    void *Ctx) {
+  unwrap(ES)->setErrorReporter(
+      [=](Error Err) { ReportError(Ctx, wrap(std::move(Err))); });
+}
+
 LLVMOrcSymbolStringPoolEntryRef
 LLVMOrcExecutionSessionIntern(LLVMOrcExecutionSessionRef ES, const char *Name) {
   return wrap(