When assigning a macro variable to itself using CALL SYMPUT and referencing the same macro variable later, an infinite recursion can occur, resulting in a stack overflow.

Example of the error that may occur:

   ERROR:  Stack overflow detected In Task [ Language Processor ]
   Exception occurred at (02501024)
   Task Traceback
   Address   Frame     (DBGHELP API Version 4.0 rev 5)
   02501024  02E3504C  sasxshel:mcn_main+0x60024
   024A51BE  02E35068  sasxshel:mcn_main+0x41BE
   024C6DE6  02E35098  sasxshel:mcn_main+0x25DE6
   ...

Here is an example of the code that might cause the recursion and the error above:

   data _null_;                             
     name='cr';                             
     value='%sysfunc(datepart(&cr),date9.)';
     call symputx(name,value,"G");          
   run;                                     
   %put &cr;

The recursion here is the macro variable name cr containing the value of &cr.

There is no current work-around other than removing the recursion.

The correct error in this case should be:

ERROR: The text expression %SYSFUNC(DATEPART(&CR),DATE9.)contains a recursive 
       reference to the macro variable CR.  The macro variable will be assigned
       the null value.

Operating System and Release Information

Product Family	Product	System	SAS Release
			Reported	Fixed*
SAS System	Base SAS	z/OS	9.2 TS2M3	9.4 TS1M0
		Microsoft® Windows® for 64-Bit Itanium-based Systems	9.2 TS2M3	9.4 TS1M0
		Microsoft Windows Server 2003 Datacenter 64-bit Edition	9.2 TS2M3	9.4 TS1M0
		Microsoft Windows Server 2003 Enterprise 64-bit Edition	9.2 TS2M3	9.4 TS1M0
		Microsoft Windows XP 64-bit Edition	9.2 TS2M3	9.4 TS1M0
		Microsoft® Windows® for x64	9.2 TS2M3	9.4 TS1M0
		Microsoft Windows Server 2003 Datacenter Edition	9.2 TS2M3	9.4 TS1M0
		Microsoft Windows Server 2003 Enterprise Edition	9.2 TS2M3	9.4 TS1M0
		Microsoft Windows Server 2003 Standard Edition	9.2 TS2M3	9.4 TS1M0
		Microsoft Windows Server 2003 for x64	9.2 TS2M3	9.4 TS1M0
		Microsoft Windows Server 2008	9.2 TS2M3	9.4 TS1M0
		Microsoft Windows Server 2008 for x64	9.2 TS2M3	9.4 TS1M0
		Microsoft Windows XP Professional	9.2 TS2M3	9.4 TS1M0
		Windows 7 Enterprise 32 bit	9.2 TS2M3
		Windows 7 Enterprise x64	9.2 TS2M3
		Windows 7 Home Premium 32 bit	9.2 TS2M3
		Windows 7 Home Premium x64	9.2 TS2M3
		Windows 7 Professional 32 bit	9.2 TS2M3
		Windows 7 Professional x64	9.2 TS2M3
		Windows 7 Ultimate 32 bit	9.2 TS2M3
		Windows 7 Ultimate x64	9.2 TS2M3
		Windows Vista	9.2 TS2M3	9.4 TS1M0
		Windows Vista for x64	9.2 TS2M3	9.4 TS1M0
		64-bit Enabled AIX	9.2 TS2M3	9.4 TS1M0
		64-bit Enabled HP-UX	9.2 TS2M3	9.4 TS1M0
		64-bit Enabled Solaris	9.2 TS2M3	9.4 TS1M0
		HP-UX IPF	9.2 TS2M3	9.4 TS1M0
		Linux	9.2 TS2M3	9.4 TS1M0
		Linux for x64	9.2 TS2M3	9.4 TS1M0
		OpenVMS on HP Integrity	9.2 TS2M3	9.4 TS1M0
		Solaris for x64	9.2 TS2M3	9.4 TS1M0

* For software releases that are not yet generally available, the Fixed Release is the software release in which the problem is planned to be fixed.

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Creating a macro variable that is equal to itself can cause a stack overflow error.

Type:	Problem Note
Priority:	low

Date Modified:	2011-11-02 16:06:45
Date Created:	2011-10-31 13:19:27