From 0ce17bae34a6c54de31b126f969d3ddd72c6bc37 Mon Sep 17 00:00:00 2001

From: Vincent Lefevre <vincent@vinc17.net>

Date: Tue, 22 Nov 2022 16:33:00 +0100

Subject: [PATCH] Fix mpfr_custom_get_kind() macro bug.

* src/mpfr.h: in the mpfr_custom_get_kind() macro, changed mpfr_ptr to

  mpfr_srcptr for _x to agree with the function prototype, in order to

  avoid a compilation failure of user code in some cases. This bug was

  introduced by commit 9f94e0311ed53d0c64d4fbca249d19cc4888027e, which

  introduced the temporary variable _x to avoid an incorrect number of

  evaluations of the x argument.

* tests/tstckintc.c: improved the tests to detect this bug.

This should fix mpfr bug #1.

Bug initially reported by FX Coudert:

  https://github.com/CGAL/cgal/issues/7064

It affects Fedora Linux:

  https://bugzilla.redhat.com/show_bug.cgi?id=2144197

---

 src/mpfr.h        |  2 +-

 tests/tstckintc.c | 10 +++++++---

 2 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/src/mpfr.h b/src/mpfr.h

index 8c8bc08d9..44d9329e3 100644

--- src/mpfr.h

+++ src/mpfr.h

@@ -1064,7 +1064,7 @@ __MPFR_DECLSPEC int mpfr_total_order_p (mpfr_srcptr, mpfr_srcptr);

 #if __GNUC__ > 2 || __GNUC_MINOR__ >= 95

 #define mpfr_custom_get_kind(x)                                         \

   __extension__ ({                                                      \

-    mpfr_ptr _x = (x);                                                  \

+    mpfr_srcptr _x = (x);                                               \

     _x->_mpfr_exp >  __MPFR_EXP_INF ?                                   \

       (mpfr_int) MPFR_REGULAR_KIND * MPFR_SIGN (_x)                     \

       : _x->_mpfr_exp == __MPFR_EXP_INF ?                               \

diff --git a/tests/tstckintc.c b/tests/tstckintc.c

index e95e81ef9..a0c4486fb 100644

--- tests/tstckintc.c

+++ tests/tstckintc.c

@@ -295,14 +295,16 @@ static void

 test_nan_inf_zero (void)

 {

   mpfr_ptr val;

+  mpfr_srcptr sval;  /* for compilation error checking */

   int sign;

   int kind;

   reset_stack ();

   val = new_mpfr (MPFR_PREC_MIN);

+  sval = val;

   mpfr_set_nan (val);

-  kind = (mpfr_custom_get_kind) (val);

+  kind = (mpfr_custom_get_kind) (sval);

   if (kind != MPFR_NAN_KIND)

     {

       printf ("mpfr_custom_get_kind error: ");

@@ -380,7 +382,8 @@ static long *

 dummy_set_si (long si)

 {

   mpfr_t x;

-  long * r = dummy_new ();

+  mpfr_srcptr px;  /* for compilation error checking */

+  long *r = dummy_new ();

   int i1, i2, i3, i4, i5;

   /* Check that the type "void *" can be used, like with the function.

@@ -405,7 +408,8 @@ dummy_set_si (long si)

   MPFR_ASSERTN (i5 == 1);

   mpfr_set_si (x, si, MPFR_RNDN);

-  r[0] = mpfr_custom_get_kind (x);

+  px = x;

+  r[0] = mpfr_custom_get_kind (px);

   /* Check that the type "void *" can be used in C, like with the function

      (forbidden in C++). Also check side effects. */

-- 

GitLab