[libcxx] [llvm] [libc++][test] `ADDITIONAL_COMPILE_FLAGS` should be a space-separated list (PR #73541)

[Nikolas Klauser via llvm-commits]

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@@ -1352,7 +1352,7 @@ def getDefaultSubstitutions(test, tmpDir, tmpBase, normalize_slashes=False):
 
     substitutions.append(("%{pathsep}", os.pathsep))
     substitutions.append(("%basename_t", baseName))
-    
+
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philnik777 wrote:

Ah, that didn't show up on my phone. It just showed that you changes the line. That's fine then I think.

https://github.com/llvm/llvm-project/pull/73541