Fix inter-mixed output when run in a multi-job build caused by the first
job overwriting the file with the first echo and all subsequent echos appending
to the end. This causes the symbol list to be defined twice leading to errant
"ld: 0711-224 WARNING: Duplicate symbol" messages from the linker.
--- a/Modules/makexp_aix	2017-07-07 22:33:27.000000000 -0500
+++ b/Modules/makexp_aix	2018-08-03 18:12:19.097066803 -0500
@@ -1,9 +1,9 @@
-#!/bin/sh
+#!/QOpenSys/usr/bin/sh
 #
 # ===========================================================================
 # FILE:         makexp_aix
 # TYPE:         standalone executable
-# SYSTEM:	AIX 3.2.5 and AIX 4
+# SYSTEM: AIX 3.2.5 and AIX 4
 #
 # DESCRIPTION:  This script creates an export list of ALL global symbols
 #               from a list of object or archive files.
@@ -18,8 +18,8 @@
 #                      <InputFile> is an object (.o) or an archive file (.a).
 #
 # HISTORY:
-#		3-Apr-1998  -- remove C++ entries of the form Class::method
-#		Vladimir Marangozov
+#  3-Apr-1998  -- remove C++ entries of the form Class::method
+#  Vladimir Marangozov
 #
 #               1-Jul-1996  -- added header information
 #               Vladimir Marangozov
@@ -32,21 +32,18 @@
 expFileName=$1
 toAppendStr=$2
 shift; shift;
-inputFiles=$*
-automsg="Generated automatically by makexp_aix"
-notemsg="NOTE: lists _all_ global symbols defined in the above file(s)."
-curwdir=`pwd`
 
+# run in a sub-shell so the output is written atomically
+(
 # Create the export file and setup the header info
-echo "#!"$toAppendStr > $expFileName
-echo "*" >> $expFileName
-echo "* $automsg  (`date -u`)" >> $expFileName
-echo "*" >> $expFileName
-echo "* Base Directory: $curwdir" >> $expFileName
-echo "* Input File(s) : $inputFiles" >> $expFileName
-echo "*" >> $expFileName
-echo "* $notemsg" >> $expFileName
-echo "*" >> $expFileName
+echo "#!"$toAppendStr
+echo "*"
+echo "* Generated automatically by makexp_aix  (`date -u`)"
+echo "*"
+echo "* Input File(s) : $*"
+echo "*"
+echo "* NOTE: lists _all_ global symbols defined in the above file(s)."
+echo "*"
 
 # Extract the symbol list using 'nm' which produces quite
 # different output under AIX 4 than under AIX 3.2.5.
@@ -71,11 +68,7 @@
 # 7. Eliminate all entries containing two colons, like Class::method
 #
 
-# Use -X32_64 if it appears to be implemented in this version of 'nm'.
-NM=/usr/ccs/bin/nm
-xopt=-X32_64
-$NM -e $xopt $1 >/dev/null 2>&1 || xopt=""
-
-$NM -Bex $xopt $inputFiles					\
-| sed -e '/ [^BDT] /d' -e '/\./d' -e 's/.* [BDT] //' -e '/::/d'	\
-| sort | uniq >> $expFileName
+/QOpenSys/usr/bin/nm -Bex -X32_64 $* \
+| sed -e '/ [^BDT] /d' -e '/\./d' -e 's/.* [BDT] //' -e '/::/d' \
+| sort | uniq
+) > $expFileName