bpo-36503: remove references to 'aix3' and 'aix4' (GH-12658)

diff --git a/Lib/test/test_fcntl.py b/Lib/test/test_fcntl.py
index acd5c7c..5d4abe3 100644
--- a/Lib/test/test_fcntl.py
+++ b/Lib/test/test_fcntl.py
@@ -34,7 +34,7 @@
                                fcntl.F_WRLCK, 0)
     elif sys.platform.startswith('gnukfreebsd'):
         lockdata = struct.pack('qqihhi', 0, 0, 0, fcntl.F_WRLCK, 0, 0)
-    elif sys.platform in ['aix3', 'aix4', 'hp-uxB', 'unixware7']:
+    elif sys.platform in ['hp-uxB', 'unixware7']:
         lockdata = struct.pack('hhlllii', fcntl.F_WRLCK, 0, 0, 0, 0, 0, 0)
     else:
         lockdata = struct.pack('hh'+start_len+'hh', fcntl.F_WRLCK, 0, 0, 0, 0, 0)
diff --git a/Misc/ACKS b/Misc/ACKS
index df6be59..19c7e43 100644
--- a/Misc/ACKS
+++ b/Misc/ACKS
@@ -476,6 +476,7 @@
 Mark Favas
 Sergey Fedoseev
 Boris Feld
+M. Felt
 Thomas Fenzl
 Niels Ferguson
 Francisco Fernández Castaño
diff --git a/Misc/NEWS.d/next/Build/2019-04-02-09-25-23.bpo-36503.0xzfkQ.rst b/Misc/NEWS.d/next/Build/2019-04-02-09-25-23.bpo-36503.0xzfkQ.rst
new file mode 100644
index 0000000..764c397
--- /dev/null
+++ b/Misc/NEWS.d/next/Build/2019-04-02-09-25-23.bpo-36503.0xzfkQ.rst
@@ -0,0 +1,2 @@
+Remove references to "aix3" and "aix4".
+Patch by M. Felt.
diff --git a/setup.py b/setup.py
index c278f08..d035960 100644
--- a/setup.py
+++ b/setup.py
@@ -1882,9 +1882,6 @@
         libs.append('tk'+ version)
         libs.append('tcl'+ version)
 
-        if HOST_PLATFORM in ['aix3', 'aix4']:
-            libs.append('ld')
-
         # Finally, link with the X11 libraries (not appropriate on cygwin)
         if not CYGWIN:
             libs.append('X11')