diff --git a/make/aix/makefiles/adlc.make b/make/aix/makefiles/adlc.make
index 4355d73b7b9943ad96df97b653883b417267ee53..8407fd8f55a789cb0568cb4ac070a3107726adf5 100644
--- a/make/aix/makefiles/adlc.make
+++ b/make/aix/makefiles/adlc.make
@@ -1,5 +1,5 @@
 #
-# Copyright (c) 1999, 2013, Oracle and/or its affiliates. All rights reserved.
+# Copyright (c) 1999, 2015, Oracle and/or its affiliates. All rights reserved.
 # DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 #
 # This code is free software; you can redistribute it and/or modify it
@@ -140,13 +140,7 @@ ADLCFLAGS += $(SYSDEFS)
 # Note "+="; it is a hook so flags.make can add more flags, like -g or -DFOO.
 ADLCFLAGS += -q -T
 
-# Normally, debugging is done directly on the ad_<arch>*.cpp files.
-# But -g will put #line directives in those files pointing back to <arch>.ad.
-# Some builds of gcc 3.2 have a bug that gets tickled by the extra #line directives
-# so skip it for 3.2 and ealier.
-ifneq "$(shell expr \( $(CC_VER_MAJOR) \> 3 \) \| \( \( $(CC_VER_MAJOR) = 3 \) \& \( $(CC_VER_MINOR) \>= 3 \) \))" "0"
 ADLCFLAGS += -g
-endif
 
 ifdef LP64
 ADLCFLAGS += -D_LP64
diff --git a/make/aix/makefiles/ppc64.make b/make/aix/makefiles/ppc64.make
index 2636a4b97429fbc5d7c88e56839b99762f8dc60a..2634d8adcc37f9284f181ab3084a662854fa99cd 100644
--- a/make/aix/makefiles/ppc64.make
+++ b/make/aix/makefiles/ppc64.make
@@ -1,6 +1,6 @@
 #
-# Copyright (c) 2004, 2013, Oracle and/or its affiliates. All rights reserved.
-# Copyright 2012, 2013 SAP AG. All rights reserved.
+# Copyright (c) 2004, 2015, Oracle and/or its affiliates. All rights reserved.
+# Copyright 2012, 2015 SAP AG. All rights reserved.
 # DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 #
 # This code is free software; you can redistribute it and/or modify it
@@ -71,9 +71,6 @@ OPT_CFLAGS += -qstrict
 OPT_CFLAGS/sharedRuntimeTrig.o = $(OPT_CFLAGS/NOOPT)
 OPT_CFLAGS/sharedRuntimeTrans.o = $(OPT_CFLAGS/NOOPT)
 
-# xlc 10.01 parameters for ipa compile.
-QIPA_COMPILE=$(if $(CXX_IS_V10),-qipa)
-
 # Xlc 10.1 parameters for aggressive optimization:
 # - qhot=level=1: Most aggressive loop optimizations.
 # - qignerrno: Assume errno is not modified by system calls.
@@ -88,7 +85,7 @@ QV10_OPT_CONSERVATIVE=$(if $(CXX_IS_V10),-qhot=level=1 -qignerrno -qinline)
 OPT_CFLAGS/synchronizer.o = $(OPT_CFLAGS) -qnoinline
 
 # Set all the xlC V10.1 options here.
-OPT_CFLAGS += $(QIPA_COMPILE) $(QV10_OPT) $(QV10_OPT_AGGRESSIVE)
+OPT_CFLAGS += $(QV10_OPT) $(QV10_OPT_AGGRESSIVE)
 
 export OBJECT_MODE=64
 
diff --git a/make/aix/makefiles/xlc.make b/make/aix/makefiles/xlc.make
index 17a71b6012447f51c824841932d422a80aaa4702..cf8d085c39ad2083925c20e49a122d03d3368527 100644
--- a/make/aix/makefiles/xlc.make
+++ b/make/aix/makefiles/xlc.make
@@ -1,6 +1,6 @@
 #
-# Copyright (c) 1999, 2013, Oracle and/or its affiliates. All rights reserved.
-# Copyright (c) 2012, 2013 SAP. All rights reserved.
+# Copyright (c) 1999, 2015, Oracle and/or its affiliates. All rights reserved.
+# Copyright (c) 2012, 2015 SAP. All rights reserved.
 # DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 #
 # This code is free software; you can redistribute it and/or modify it
@@ -34,13 +34,17 @@ HOSTCC  = $(CC)
 
 AS  = $(CC) -c
 
-# get xlc version
-CXX_VERSION   := $(shell $(CXX) -qversion 2>&1 | sed -n 's/.*Version: \([0-9.]*\)/\1/p')
+# get xlc version which comes as VV.RR.MMMM.LLLL where 'VV' is the version,
+# 'RR' is the release, 'MMMM' is the modification and 'LLLL' is the level.
+# We only use 'VV.RR.LLLL' to avoid integer overflows in bash when comparing
+# the version numbers (some shells only support 32-bit integer compares!).
+CXX_VERSION := $(shell $(CXX) -qversion 2>&1 | \
+                   sed -n 's/.*Version: \([0-9]\{2\}\).\([0-9]\{2\}\).[0-9]\{4\}.\([0-9]\{4\}\)/\1\2\3/p')
 
 # xlc 08.00.0000.0023 and higher supports -qtune=balanced
-CXX_SUPPORTS_BALANCED_TUNING=$(shell if [ $(subst .,,$(CXX_VERSION)) -ge 080000000023 ] ; then echo "true" ; fi)
+CXX_SUPPORTS_BALANCED_TUNING := $(shell if [ $(CXX_VERSION) -ge 08000023 ] ; then echo "true" ; fi)
 # xlc 10.01 is used with aggressive optimizations to boost performance
-CXX_IS_V10=$(shell if [ $(subst .,,$(CXX_VERSION)) -ge 100100000000 ] ; then echo "true" ; fi)
+CXX_IS_V10 := $(shell if [ $(CXX_VERSION) -ge 10010000 ] ; then echo "true" ; fi)
 
 # check for precompiled headers support