[llvm] [SPIRV] Error in backend for vararg functions (PR #169111)

[Juan Manuel Martinez Caamaño via llvm-commits]

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@@ -970,8 +970,11 @@ SPIRVType *SPIRVGlobalRegistry::getOpTypeForwardPointer(
 }
 
 SPIRVType *SPIRVGlobalRegistry::getOpTypeFunction(
-    SPIRVType *RetType, const SmallVectorImpl<SPIRVType *> &ArgTypes,
+    const FunctionType *Ty, SPIRVType *RetType,
+    const SmallVectorImpl<SPIRVType *> &ArgTypes,
     MachineIRBuilder &MIRBuilder) {
+  if (Ty->isVarArg())
+    reportFatalUsageError("SPIR-V does not support variadic functions");
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jmmartinez wrote:

I'm wondering if we should use a richer error reporting API for this.

More precisely, raising a diagnostic through `LLVMContext::diagnose` of type `DiagnosticInfoUnsupported`. To raise the line info to the user if it is available.

https://github.com/llvm/llvm-project/pull/169111