[llvm] [LLVM] [Support] Query the terminal width using the termios API (PR #143514)

[Fangrui Song via llvm-commits]

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@@ -304,31 +307,41 @@ bool Process::FileDescriptorIsDisplayed(int fd) {
 #endif
 }
 
-static unsigned getColumns() {
+static unsigned getColumns([[maybe_unused]] int FileID) {
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MaskRay wrote:

We don't use maybe_unused for arguments. 

https://github.com/llvm/llvm-project/pull/143514