[llvm] [SPIRV] Fix code quality issues. (PR #152005)

[Nathan Gauër via llvm-commits]

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@@ -591,7 +592,8 @@ void SPIRVAsmPrinter::outputAnnotations(const Module &M) {
           cast<GlobalVariable>(CS->getOperand(1)->stripPointerCasts());
 
       StringRef AnnotationString;
-      getConstantStringInfo(GV, AnnotationString);
+      bool Success = getConstantStringInfo(GV, AnnotationString);
+      assert(Success && "Failed to get annotation string");
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Keenuts wrote:

You'll need to `(void)Success` otherwise warning when building with nassert

https://github.com/llvm/llvm-project/pull/152005