From e31f0a8d0f55d75bc4e36e1c2e5413f5d45d894e Mon Sep 17 00:00:00 2001
From: Houtan Bastani <houtan@dynare.org>
Date: Mon, 5 Sep 2016 17:19:09 +0200
Subject: [PATCH] macroprocessor: stop with error when division by zero is
encountered. closes #1278
---
doc/dynare.texi | 7 +++++--
preprocessor/macro/MacroBison.yy | 9 +++++++--
preprocessor/macro/MacroValue.hh | 3 ++-
3 files changed, 14 insertions(+), 5 deletions(-)
diff --git a/doc/dynare.texi b/doc/dynare.texi
index f825a357f8..40aba5129b 100644
--- a/doc/dynare.texi
+++ b/doc/dynare.texi
@@ -9699,8 +9699,11 @@ String literals have to be enclosed between @strong{double} quotes
elements are separated by commas (like @code{[1,2,3]} or @code{["US",
"EA"]}).
-Note that there is no boolean type: @emph{false} is
-represented by integer zero and @emph{true} is any non-null integer.
+Note that there is no boolean type: @emph{false} is represented by integer zero
+and @emph{true} is any non-null integer. Further note that, as the
+macro-processor cannot handle non-integer real numbers, integer division
+results in the quotient with the fractional part truncated (hence,
+@math{5/3=3/3=1}).
The following operators can be used on integers:
@itemize
diff --git a/preprocessor/macro/MacroBison.yy b/preprocessor/macro/MacroBison.yy
index 2bd8072a4c..27c0e4b28c 100644
--- a/preprocessor/macro/MacroBison.yy
+++ b/preprocessor/macro/MacroBison.yy
@@ -1,5 +1,5 @@
/*
- * Copyright (C) 2008-2014 Dynare Team
+ * Copyright (C) 2008-2016 Dynare Team
*
* This file is part of Dynare.
*
@@ -150,7 +150,12 @@ expr : INTEGER
| expr TIMES expr
{ TYPERR_CATCH($$ = *$1 * *$3, @$); }
| expr DIVIDE expr
- { TYPERR_CATCH($$ = *$1 / *$3, @$); }
+ {
+ if (dynamic_cast<const IntMV *>($3) != NULL
+ && ((IntMV *)$3)->get_int_value() == 0)
+ driver.error(@$, "Division by zero");
+ TYPERR_CATCH($$ = *$1 / *$3, @$);
+ }
| expr LESS expr
{ TYPERR_CATCH($$ = *$1 < *$3, @$); }
| expr GREATER expr
diff --git a/preprocessor/macro/MacroValue.hh b/preprocessor/macro/MacroValue.hh
index 2501647812..c9da9c3ddf 100644
--- a/preprocessor/macro/MacroValue.hh
+++ b/preprocessor/macro/MacroValue.hh
@@ -1,5 +1,5 @@
/*
- * Copyright (C) 2008-2013 Dynare Team
+ * Copyright (C) 2008-2016 Dynare Team
*
* This file is part of Dynare.
*
@@ -158,6 +158,7 @@ public:
If mv2 < mv1, returns an empty range (for consistency with MATLAB).
*/
static const MacroValue *new_range(MacroDriver &driver, const MacroValue *mv1, const MacroValue *mv2) throw (TypeError);
+ inline int get_int_value() const { return value; };
};
//! Represents a string value in macro language
--
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