Don't call SetEnvironmentVariable() when removing an environment variable,

as this seems to crash on at least some versions of MingW. Our current usage
of this function does not require it, so it should be ok to ignore.

1 files changed, 12 insertions, 6 deletions

diff --git a/src/port/win32env.c b/src/port/win32env.c
index 7533549608..36888286b7 100644
--- a/src/port/win32env.c
+++ b/src/port/win32env.c
@@ -10,7 +10,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/port/win32env.c,v 1.1 2009/01/21 10:30:02 mha Exp $
+ *	  $PostgreSQL: pgsql/src/port/win32env.c,v 1.2 2009/02/12 12:53:34 mha Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -64,12 +64,18 @@ pgwin32_putenv(const char *envval)
 		return -1;
 	*cp = '\0';
 	cp++;
-	if (strlen(cp) == 0)
-		cp = NULL;
-	if (!SetEnvironmentVariable(envcpy, cp))
+	if (strlen(cp))
 	{
-		free(envcpy);
-		return -1;
+		/*
+		 * Only call SetEnvironmentVariable() when we are adding a variable,
+		 * not when removing it. Calling it on both crashes on at least certain
+		 * versions of MingW.
+		 */
+		if (!SetEnvironmentVariable(envcpy, cp))
+		{
+			free(envcpy);
+			return -1;
+		}
 	}
 	free(envcpy);