From aa9247b3c3dfea8b1127d739b486c2e5bb8e54ce Mon Sep 17 00:00:00 2001
From: John Darrington <john@darrington.wattle.id.au>
Date: Wed, 28 Sep 2011 19:55:45 +0200
Subject: [PATCH] Fixed a crash in REGRESSION when there were no non-missing
 values.

---
 src/language/stats/regression.q    |  8 ++++++--
 tests/language/stats/regression.at | 24 ++++++++++++++++++++++++
 2 files changed, 30 insertions(+), 2 deletions(-)

diff --git a/src/language/stats/regression.q b/src/language/stats/regression.q
index c41f9e78..4ef12c98 100644
--- a/src/language/stats/regression.q
+++ b/src/language/stats/regression.q
@@ -792,6 +792,7 @@ identify_indep_vars (const struct variable **indep_vars,
     }
   return n_indep_vars;
 }
+
 static double
 fill_covariance (gsl_matrix *cov, struct covariance *all_cov, 
 		 const struct variable **vars,
@@ -804,12 +805,15 @@ fill_covariance (gsl_matrix *cov, struct covariance *all_cov,
   size_t dep_subscript;
   size_t *rows;
   const gsl_matrix *ssizes;
-  gsl_matrix *cm;
   const gsl_matrix *mean_matrix;
   const gsl_matrix *ssize_matrix;
   double result = 0.0;
   
-  cm = covariance_calculate_unnormalized (all_cov);
+  gsl_matrix *cm = covariance_calculate_unnormalized (all_cov);
+
+  if ( cm == NULL)
+    return 0;
+
   rows = xnmalloc (cov->size1 - 1, sizeof (*rows));
   
   for (i = 0; i < n_all_vars; i++)
diff --git a/tests/language/stats/regression.at b/tests/language/stats/regression.at
index 0ea3efc8..81bbce43 100644
--- a/tests/language/stats/regression.at
+++ b/tests/language/stats/regression.at
@@ -1590,3 +1590,27 @@ Table: Coefficients
 ,,,,,,
 ])
 AT_CLEANUP
+
+AT_SETUP([REGRESSION no crash on all missing])
+AT_DATA([regcrash.sps], [dnl
+data list list /x * y.
+begin data.
+ . .
+ . .
+ . .
+ . .
+ . .
+ . .
+ . .
+ . .
+ . .
+ . .
+end data.
+
+
+regression /variables=x y /dependent=y.
+])
+
+AT_CHECK([pspp -o pspp.csv regcrash.sps], [1], [ignore], [ignore])
+
+AT_CLEANUP
-- 
2.30.2