Increase define recursions before error

Changes

@@ -3,6 +3,10 @@ Revision history for Verilator
 The contributors that suggested a given feature are shown in [].  [by ...]
 indicates the contributor was also the author of the fix; Thanks!
 
+* Verilator 3.8****
+
+**** Increase define recursions before error.  [Paul Liu]
+
 * Verilator 3.803 2010/07/10
 
 ***  Fix preprocessor preservation of newlines across macro substitutions.

src/V3PreProc.h

@@ -48,7 +48,7 @@ protected:
 public:
     // CONSTANTS
     enum MiscConsts {
-	DEFINE_RECURSION_LEVEL_MAX = 50,	// How many `def substitutions before an error
+	DEFINE_RECURSION_LEVEL_MAX = 1000,	// How many `def substitutions before an error
 	INCLUDE_DEPTH_MAX = 500,		// How many `includes deep before an error
 	NEWLINES_VS_TICKLINE = 20		// Use `line in place of this many newlines
     };