From fad701f04b435a42e2feabd90174274f04a23d4d Mon Sep 17 00:00:00 2001
From: John Darrington <john@darrington.wattle.id.au>
Date: Sun, 8 Aug 2010 11:39:16 +0200
Subject: [PATCH] Aggregate: Fixed bug when attempting to create duplicate
 variable

This change fixes a segfault which occured if AGGREGATE MODE=ADDVARIABLES
attempted to create a variable which already exists in the dictionary.
Added a test to check for this bug.
---
 src/language/stats/aggregate.c    | 16 ++++++++-----
 tests/language/stats/aggregate.at | 40 +++++++++++++++++++++++++++++++
 2 files changed, 50 insertions(+), 6 deletions(-)

diff --git a/src/language/stats/aggregate.c b/src/language/stats/aggregate.c
index b2132ec71a..7625a6f1a7 100644
--- a/src/language/stats/aggregate.c
+++ b/src/language/stats/aggregate.c
@@ -637,12 +637,16 @@ parse_aggregate_functions (struct lexer *lexer, const struct dictionary *dict,
                 struct fmt_spec f;
 		v->src = NULL;
 		destvar = dict_create_var (agr->dict, dest[i], 0);
-                if (func_index == N && dict_get_weight (dict) != NULL)
-                  f = fmt_for_output (FMT_F, 8, 2);
-                else
-                  f = function->format;
-                var_set_both_formats (destvar, &f);
-	      }
+		if (destvar != NULL)
+		  {
+		    if ((func_index == N || func_index == NMISS)
+			&& dict_get_weight (dict) != NULL)
+		      f = fmt_for_output (FMT_F, 8, 2);
+		    else
+		      f = function->format;
+		    var_set_both_formats (destvar, &f);
+		  }
+	    }
 
 	    if (!destvar)
 	      {
diff --git a/tests/language/stats/aggregate.at b/tests/language/stats/aggregate.at
index 3c10d3ad40..da078f84d1 100644
--- a/tests/language/stats/aggregate.at
+++ b/tests/language/stats/aggregate.at
@@ -249,3 +249,43 @@ x,cn,y,sum,mean,median
 ])
 
 AT_CLEANUP
+
+
+AT_SETUP([AGGREGATE buggy duplicate variables])
+dnl Test for a bug which crashed when duplicated
+dnl variables were attempted.
+AT_DATA([dup-variables.sps],
+  [DATA LIST NOTABLE LIST /x * .
+begin data
+1
+1
+1
+1
+2
+2
+2
+3
+3
+3
+3
+3
+3
+end data.
+
+AGGREGATE OUTFILE=* MODE=ADDVARIABLES
+	/BREAK= x
+	/N_BREAK = N.
+
+AGGREGATE OUTFILE=* MODE=ADDVARIABLES
+	/BREAK= x
+	/N_BREAK = N.
+])
+
+AT_CHECK([pspp -O format=csv dup-variables.sps], [1],
+["dup-variables.sps:24: error: AGGREGATE: Variable name N_BREAK is not unique within the aggregate file dictionary, which contains the aggregate variables and the break variables."
+
+dup-variables.sps:24: error: Stopping syntax file processing here to avoid a cascade of dependent command failures.
+])
+
+
+AT_CLEANUP
\ No newline at end of file
-- 
2.30.2