[clang] [lld] [llvm] [Windows] Add support for emitting PGO/LTO magic strings in the Windows PE debug directory (PR #114260)

[Fangrui Song via cfe-commits]

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@@ -77,6 +77,12 @@ static unsigned char dosProgram[] = {
 static_assert(sizeof(dosProgram) % 8 == 0,
               "DOSProgram size must be multiple of 8");
 
+static char ltcg[] = "LTCG";
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MaskRay wrote:

`constexpr char ...[]`

constexpr/const make this internal linkage, making static unneeded

https://github.com/llvm/llvm-project/pull/114260