MPFR division by zero is now a fatal error.

3 files changed, 17 insertions, 1 deletions

diff --git a/ChangeLog b/ChangeLog
index 73896243..c598dac5 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -5,6 +5,13 @@
 	code into line with regular code. Bug report from Neil Ormos
 	in the help-gawk list.
 
+	Unrelated:
+
+	* mpfr.c (do_mpfr_int_div, mpg_div, mpg_mod): If dividing by
+	zero, print a fatal error messages. Brings MPFR code into line
+	with the regular code. Thanks to Peng Yu for noticing the bug, in
+	the help-gawk list.
+
 2021-07-23         Arnold D. Robbins     <arnold@skeeve.com>
 
 	* awk.h (exec_count_t): Add typedef for Vax VMS C and everyone else.
diff --git a/NEWS b/NEWS
index 7b9c4d21..9b420f94 100644
--- a/NEWS
+++ b/NEWS
@@ -53,7 +53,10 @@ Changes from 5.1.0 to 5.1.1
 14. The manual has been updated with much more information about what is
     and is not a bug, and the changes in the gawk mailing lists.
 
-15. There have been numerous minor code cleanups and bug fixes. See the
+15. Similar to item #4 above, division by zero is now fatal in MPFR
+    mode, as it is in regular mode.
+
+16. There have been numerous minor code cleanups and bug fixes. See the
     ChangeLog for details.
 
 Changes from 5.0.1 to 5.1.0
diff --git a/mpfr.c b/mpfr.c
index cf18288a..4010d0c1 100644
--- a/mpfr.c
+++ b/mpfr.c
@@ -1509,6 +1509,8 @@ mpg_div(NODE *t1, NODE *t2)
 		mpfr_ptr p1, p2;
 		p1 = MP_FLOAT(t1);
 		p2 = MP_FLOAT(t2);
+		if (mpfr_zero_p(p2))
+			fatal(_("division by zero attempted"));
 		r = mpg_float();
 		tval = mpfr_div(r->mpg_numbr, p1, p2, ROUND_MODE);
 		IEEE_FMT(r->mpg_numbr, tval);
@@ -1542,6 +1544,8 @@ mpg_mod(NODE *t1, NODE *t2)
 		 */
 		NODE *dummy_quotient;
 
+		if (mpz_sgn(t2->mpg_i) == 0)
+			fatal(_("division by zero attempted"));
 		r = mpg_integer();
 		dummy_quotient = mpg_integer();
 		mpz_tdiv_qr(dummy_quotient->mpg_i, r->mpg_i, t1->mpg_i, t2->mpg_i);
@@ -1550,6 +1554,8 @@ mpg_mod(NODE *t1, NODE *t2)
 		mpfr_ptr p1, p2;
 		p1 = MP_FLOAT(t1);
 		p2 = MP_FLOAT(t2);
+		if (mpfr_zero_p(p2))
+			fatal(_("division by zero attempted in `%%'"));
 		r = mpg_float();
 		tval = mpfr_fmod(r->mpg_numbr, p1, p2, ROUND_MODE);
 		IEEE_FMT(r->mpg_numbr, tval);