[clang] [clang][Driver][test] Specify output path in modules-driver-depscan-log.cpp (PR #222209)

[via cfe-commits]

zeroomega wrote:

We are seeing "clang/test/Driver/modules-driver-depscan-log.cpp" failing on our mac builders after this PR was landed. error message:
```
FAIL: Clang :: Driver/modules-driver-depscan-log.cpp (14555 of 25664)
******************** TEST 'Clang :: Driver/modules-driver-depscan-log.cpp' FAILED ********************
Exit Code: 1

Command Output (stdout):
--
# RUN: at line 4
rm -rf /Users/swarming/b/s/w/ir/x/w/llvm_build/tools/clang/test/Driver/Output/modules-driver-depscan-log.cpp.tmp
# executed command: rm -rf /Users/swarming/b/s/w/ir/x/w/llvm_build/tools/clang/test/Driver/Output/modules-driver-depscan-log.cpp.tmp
# RUN: at line 5
split-file /Users/swarming/b/s/w/ir/x/w/llvm-llvm-project/clang/test/Driver/modules-driver-depscan-log.cpp /Users/swarming/b/s/w/ir/x/w/llvm_build/tools/clang/test/Driver/Output/modules-driver-depscan-log.cpp.tmp
# executed command: split-file /Users/swarming/b/s/w/ir/x/w/llvm-llvm-project/clang/test/Driver/modules-driver-depscan-log.cpp /Users/swarming/b/s/w/ir/x/w/llvm_build/tools/clang/test/Driver/Output/modules-driver-depscan-log.cpp.tmp
# RUN: at line 7
/Users/swarming/b/s/w/ir/x/w/llvm_build/bin/clang -c -std=c++23 -fmodules-driver -fdepscan-log-path=/Users/swarming/b/s/w/ir/x/w/llvm_build/tools/clang/test/Driver/Output/modules-driver-depscan-log.cpp.tmp/scan.log    /Users/swarming/b/s/w/ir/x/w/llvm_build/tools/clang/test/Driver/Output/modules-driver-depscan-log.cpp.tmp/A.cppm -o /Users/swarming/b/s/w/ir/x/w/llvm_build/tools/clang/test/Driver/Output/modules-driver-depscan-log.cpp.tmp/A.o
# executed command: /Users/swarming/b/s/w/ir/x/w/llvm_build/bin/clang -c -std=c++23 -fmodules-driver -fdepscan-log-path=/Users/swarming/b/s/w/ir/x/w/llvm_build/tools/clang/test/Driver/Output/modules-driver-depscan-log.cpp.tmp/scan.log /Users/swarming/b/s/w/ir/x/w/llvm_build/tools/clang/test/Driver/Output/modules-driver-depscan-log.cpp.tmp/A.cppm -o /Users/swarming/b/s/w/ir/x/w/llvm_build/tools/clang/test/Driver/Output/modules-driver-depscan-log.cpp.tmp/A.o
# .---command stderr------------
# | clang: error: cannot specify -o when generating multiple output files
# `-----------------------------
# error: command failed with exit status: 1

--

********************
```
Example of failed task: https://ci.chromium.org/ui/p/fuchsia/builders/toolchain.ci/clang-mac-arm64/b8671175768598745089?
Our mac build uses libcxx and it might probably the reason why this issue is currently not affecting LLVM's own post submit builders.

We suspect this patch unintentionally uncovered a bug in clang driver. When output format is Mach-O.


https://github.com/llvm/llvm-project/pull/222209