[libc-commits] [libc] libc/cmake: don't fail if LLVM_VERSION_SUFFIX isn't defined (PR #126359)

[Joseph Huber via libc-commits]

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@@ -51,7 +51,11 @@ set(LIBC_KERNEL_HEADERS "/usr/include" CACHE STRING "Path to Linux kernel header
 # Defining a global namespace to enclose all libc functions.
 set(default_namespace "__llvm_libc")
 if(LLVM_VERSION_MAJOR)
-  string(REPLACE "-" "" NS_LLVM_VERSION_SUFFIX ${LLVM_VERSION_SUFFIX})
+  if(DEFINED LLVM_VERSION_SUFFIX AND NOT "${LLVM_VERSION_SUFFIX}" STREQUAL "")
+    string(REPLACE "-" "" NS_LLVM_VERSION_SUFFIX "${LLVM_VERSION_SUFFIX}")
+  else()
+    set(NS_LLVM_VERSION_SUFFIX "")
+  endif()
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jhuber6 wrote:

But the empty string is an argument? If `LLVM_VERSION_SUFFIX` is not defined then `${LLVM_VERSION_SUFFIX}` expands to nothing, but `"${LLVM_VERSION_SUFFIX}"` expands to `""`, which is just asking to replace strings in an empty string.

https://github.com/llvm/llvm-project/pull/126359