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

[Nathan Gauër via llvm-commits]

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@@ -463,8 +463,9 @@ std::string getOclOrSpirvBuiltinDemangledName(StringRef Name) {
     DemangledNameLenStart = NameSpaceStart + 11;
   }
   Start = Name.find_first_not_of("0123456789", DemangledNameLenStart);
-  Name.substr(DemangledNameLenStart, Start - DemangledNameLenStart)
-      .getAsInteger(10, Len);
+  bool Error = Name.substr(DemangledNameLenStart, Start - DemangledNameLenStart)
+                   .getAsInteger(10, Len);
+  assert(!Error && "Failed to parse demangled name length");
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Keenuts wrote:

Same, will raise a warning when building with no assertions

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