[libc] [llvm] [libc] add basic arena allocator (PR #121173)

[Nick Desaulniers via llvm-commits]

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@@ -141,6 +141,12 @@ functions:
       - type: int
       - type: __getoptargv_t
       - type: const char *
+  - name: getpagesize
+    standards:
+      - POSIX
+    return_type: int
+    arguments:
+      - type: void
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nickdesaulniers wrote:

Sorry, did you move it to a distinct PR? or not yet?

https://github.com/llvm/llvm-project/pull/121173