From d4552af39b5006aa5f3a9d2d0c67411464ec54b9 Mon Sep 17 00:00:00 2001
From: Andrew Johnson <anj@aps.anl.gov>
Date: Mon, 17 Apr 2017 11:47:21 -0500
Subject: [PATCH] Fix and test for macLib losing error status

Problem found & diagnosed by Mark Rivers.
---
 src/libCom/macLib/macCore.c  | 4 ++--
 src/libCom/test/macLibTest.c | 5 ++++-
 2 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/src/libCom/macLib/macCore.c b/src/libCom/macLib/macCore.c
index f550ed7dc..ba1c84fa4 100644
--- a/src/libCom/macLib/macCore.c
+++ b/src/libCom/macLib/macCore.c
@@ -857,9 +857,9 @@ static void refer ( MAC_HANDLE *handle, MAC_ENTRY *entry, int level,
         if ( !refentry->visited ) {
             /* reference is good, use it */
             if ( !handle->dirty ) {
-                /* copy the already-expanded value, and its error status! */
+                /* copy the already-expanded value, merge any error status */
                 cpy2val( refentry->value, &v, valend );
-                entry->error = refentry->error;
+                entry->error = entry->error || refentry->error;
             } else {
                 /* translate raw value */
                 const char *rv = refentry->rawval;
diff --git a/src/libCom/test/macLibTest.c b/src/libCom/test/macLibTest.c
index 1f00a6ac7..7f1e2c544 100644
--- a/src/libCom/test/macLibTest.c
+++ b/src/libCom/test/macLibTest.c
@@ -65,7 +65,7 @@ static void ovcheck(void)
 
 MAIN(macLibTest)
 {
-    testPlan(89);
+    testPlan(91);
 
     if (macCreateHandle(&h, NULL))
         testAbort("macCreateHandle() failed");
@@ -203,6 +203,9 @@ MAIN(macLibTest)
         /* STR2 = "VAL2" */
     check("${FOO}", " VAL2");
 
+    check("$(FOO)$(FOO1)", "!VAL2$(FOO1,undefined)");
+    check("$(FOO1)$(FOO)", "!$(FOO1,undefined)VAL2");
+
     macPutValue(h, "BAR","${FOO}");
         /* FOO = "${BAR}" */
         /* BAR = "${FOO}" */