[libcxx-commits] [libcxx] [libc++][AIX] Define _LARGE_FILES to fix offset_range.pass test on 32-bit AIX (PR #189540)

[via libcxx-commits]

https://github.com/Himadhith created https://github.com/llvm/llvm-project/pull/189540

This patch fixes the `offset_range.pass.cpp` test failure on 32-bit AIX by defining `_LARGE_FILES` before including system headers.
The change should affect only the C library headers and since it is being set only for this test, there should not be any ABI modifications as well.

>From ce2f277ae95dbb92d92001f5d6d96c3d220aaa22 Mon Sep 17 00:00:00 2001
From: himadhith <himadhith.v at ibm.com>
Date: Tue, 31 Mar 2026 03:33:52 -0400
Subject: [PATCH] [libc++][AIX] Define _LARGE_FILES to fix offset_range.pass
 test on 32-bit AIX

---
 .../fstreams/ifstream.members/offset_range.pass.cpp        | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/libcxx/test/std/input.output/file.streams/fstreams/ifstream.members/offset_range.pass.cpp b/libcxx/test/std/input.output/file.streams/fstreams/ifstream.members/offset_range.pass.cpp
index 9fc3cb4a94478..149aa872c5c17 100644
--- a/libcxx/test/std/input.output/file.streams/fstreams/ifstream.members/offset_range.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/fstreams/ifstream.members/offset_range.pass.cpp
@@ -18,15 +18,14 @@
 //
 // XFAIL: target={{i686|arm.*}}-{{.+}}-android{{.*}}
 
-// Writing the >4 GB test file fails on 32 bit AIX.
-//
-// XFAIL: target=powerpc-{{.+}}-aix{{.*}}
-
 // By default, off_t is typically a 32-bit integer on ARMv7 Linux systems,
 // meaning it can represent file sizes up to 2GB (2^31 bytes) only.
 //
 // UNSUPPORTED: target=armv7-unknown-linux-gnueabihf
 
+#if defined(_AIX) && !defined(__64BIT__) && !defined(_LARGE_FILES)
+#  define _LARGE_FILES 1
+#endif
 #include <fstream>
 #include <iostream>
 #include <cassert>