[clang] [clang-cl] Add new option `/pathmap:<from>=<to>` to replace the path prefix <from> with <to>. (PR #198664)

[Daniel Paoliello via cfe-commits]

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@@ -0,0 +1,10 @@
+// RUN: %clang_cl -E /pathmap:%p=x:/path-to/ %s | FileCheck %s --check-prefix CHECK-REPRODUCABLE
+// CHECK-REPRODUCABLE: filename: "x:\\path-to\\cl-pathmap.c"
+// CHECK-REPRODUCABLE-NOT: filename:
+// CHECK-REPRODUCABLE-NOT: filename: "x:/path-to/cl-pathmap.c"
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dpaoliello wrote:

Redundant with the CHECK line above: if there is no `filename:` there can't be this line.

https://github.com/llvm/llvm-project/pull/198664