[clang] [llvm] [SystemZ][z/OS] Add new openFileForReadBinary function, and pass IsText parameter to getBufferForFile (PR #111723)

[kadir çetinkaya via llvm-commits]

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@@ -54,7 +54,9 @@ std::unique_ptr<HeaderMap> HeaderMap::Create(FileEntryRef FE, FileManager &FM) {
   unsigned FileSize = FE.getSize();
   if (FileSize <= sizeof(HMapHeader)) return nullptr;
 
-  auto FileBuffer = FM.getBufferForFile(FE);
+  auto FileBuffer =
+      FM.getBufferForFile(FE, /*IsVolatile=*/false,
+                          /*RequiresNullTerminator=*/true, /*IsText=*/false);
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kadircet wrote:

i think it'd be great to have a test case for this that actually fails (even if only in zOS).

https://github.com/llvm/llvm-project/pull/111723