[clang] [Driver] Honor /Fo when deriving the split-dwarf .dwo path (PR #199613)

[Haohai Wen via cfe-commits]

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@@ -57,6 +57,12 @@
 // SINGLE_WITH_FILENAME: "-split-dwarf-file" "{{.*}}foo.o"
 // SINGLE_WITH_FILENAME-NOT: "-split-dwarf-output"
 
+/// /Fo drives the .dwo path so it lands next to the .obj.
+// RUN: %clang_cl -### -c --target=x86_64-unknown-windows-msvc -gdwarf -gsplit-dwarf /Foobj/out.obj -- %s 2>&1 | FileCheck %s --check-prefix=SPLIT_SLASH_FO
+// RUN: %clang_cl -### -c --target=x86_64-unknown-windows-msvc -gdwarf -gsplit-dwarf /Fo:obj/out.obj -- %s 2>&1 | FileCheck %s --check-prefix=SPLIT_SLASH_FO
+
+// SPLIT_SLASH_FO:      "-split-dwarf-file" "obj{{[/\\]}}out.dwo" "-split-dwarf-output" "obj{{[/\\]}}out.dwo"
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HaohaiWen wrote:

Addressed.

https://github.com/llvm/llvm-project/pull/199613