[compiler-rt] [Compiler-rt] Fix wrong assignment in compiler_rt (PR #164713)

[Yuxuan Chen via llvm-commits]

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@@ -36,14 +36,14 @@ enum VendorSignatures {
   SIG_AMD = 0x68747541,   // Auth
 };
 
-enum ProcessorVendors {
+enum ProcessorVendors : unsigned int {
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yuxuanchen1997 wrote:

Is this ISO-compliant C? In [C17 standard](https://www.open-std.org/jtc1/sc22/wg14/www/docs/n2310.pdf) 6.7.2.2 _enum-specifier_ has no _enum-base_ which I am afraid that is only a C++11 feature. 

https://github.com/llvm/llvm-project/pull/164713