From 7233c428ec122c121b5d6dac1b339ebf54960e64 Mon Sep 17 00:00:00 2001
From: V-for-Vasili <vasili.skurydzin@protonmail.com>
Date: Wed, 6 Apr 2022 08:07:05 -0400
Subject: [PATCH] build: fix AIX xlc autotools build (#3588)

---
 configure.ac            |  4 +++-
 m4/libuv-check-flags.m4 | 14 ++++++++++++++
 2 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/configure.ac b/configure.ac
index a9012d40..808c949d 100644
--- a/configure.ac
+++ b/configure.ac
@@ -28,7 +28,9 @@ AM_PROG_CC_C_O
 CC_ATTRIBUTE_VISIBILITY([default], [
   CC_FLAG_VISIBILITY([CFLAGS="${CFLAGS} -fvisibility=hidden"])
 ])
-CC_CHECK_CFLAGS_APPEND([-fno-strict-aliasing])
+# Xlc has a flag "-f<filename>". Need to use CC_CHECK_FLAG_SUPPORTED_APPEND so
+# we exclude -fno-strict-aliasing for xlc
+CC_CHECK_FLAG_SUPPORTED_APPEND([-fno-strict-aliasing])
 CC_CHECK_CFLAGS_APPEND([-g])
 CC_CHECK_CFLAGS_APPEND([-std=gnu89])
 CC_CHECK_CFLAGS_APPEND([-Wall])
diff --git a/m4/libuv-check-flags.m4 b/m4/libuv-check-flags.m4
index 9d0aad82..2a01308d 100644
--- a/m4/libuv-check-flags.m4
+++ b/m4/libuv-check-flags.m4
@@ -104,6 +104,20 @@ AC_DEFUN([CC_CHECK_LDFLAGS], [
     [$2], [$3])
 ])
 
+dnl Check if flag is supported by both compiler and linker
+dnl If so, append it to AM_CFLAGS
+dnl CC_CHECK_FLAG_SUPPORTED_APPEND([FLAG])
+
+AC_DEFUN([CC_CHECK_FLAG_SUPPORTED_APPEND], [
+  CC_CHECK_CFLAGS([$1],
+    [CC_CHECK_LDFLAGS([$1],
+        [AM_CFLAGS="$AM_CFLAGS $1";
+         DEBUG_CFLAGS="$DEBUG_CFLAGS $1";
+         AC_SUBST([AM_CFLAGS])
+    ])
+  ])
+])
+
 dnl define the LDFLAGS_NOUNDEFINED variable with the correct value for
 dnl the current linker to avoid undefined references in a shared object.
 AC_DEFUN([CC_NOUNDEFINED], [