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-rw-r--r--patches/mpfr/3.0.1/120-rec_sqrt-carry.patch76
1 files changed, 76 insertions, 0 deletions
diff --git a/patches/mpfr/3.0.1/120-rec_sqrt-carry.patch b/patches/mpfr/3.0.1/120-rec_sqrt-carry.patch
new file mode 100644
index 0000000..0367d84
--- /dev/null
+++ b/patches/mpfr/3.0.1/120-rec_sqrt-carry.patch
@@ -0,0 +1,76 @@
+diff -Naurd mpfr-3.0.1-a/PATCHES mpfr-3.0.1-b/PATCHES
+--- mpfr-3.0.1-a/PATCHES 2011-05-04 11:18:33.000000000 +0000
++++ mpfr-3.0.1-b/PATCHES 2011-05-04 11:18:33.000000000 +0000
+@@ -0,0 +1 @@
++rec_sqrt-carry
+diff -Naurd mpfr-3.0.1-a/VERSION mpfr-3.0.1-b/VERSION
+--- mpfr-3.0.1-a/VERSION 2011-04-12 10:50:02.000000000 +0000
++++ mpfr-3.0.1-b/VERSION 2011-05-04 11:18:33.000000000 +0000
+@@ -1 +1 @@
+-3.0.1-p1
++3.0.1-p2
+diff -Naurd mpfr-3.0.1-a/mpfr.h mpfr-3.0.1-b/mpfr.h
+--- mpfr-3.0.1-a/mpfr.h 2011-04-12 10:50:02.000000000 +0000
++++ mpfr-3.0.1-b/mpfr.h 2011-05-04 11:18:33.000000000 +0000
+@@ -27,7 +27,7 @@
+ #define MPFR_VERSION_MAJOR 3
+ #define MPFR_VERSION_MINOR 0
+ #define MPFR_VERSION_PATCHLEVEL 1
+-#define MPFR_VERSION_STRING "3.0.1-p1"
++#define MPFR_VERSION_STRING "3.0.1-p2"
+
+ /* Macros dealing with MPFR VERSION */
+ #define MPFR_VERSION_NUM(a,b,c) (((a) << 16L) | ((b) << 8) | (c))
+diff -Naurd mpfr-3.0.1-a/rec_sqrt.c mpfr-3.0.1-b/rec_sqrt.c
+--- mpfr-3.0.1-a/rec_sqrt.c 2011-04-04 10:19:18.000000000 +0000
++++ mpfr-3.0.1-b/rec_sqrt.c 2011-05-04 11:18:33.000000000 +0000
+@@ -375,20 +375,37 @@
+ MPFR_ASSERTD(un == ln + 1 || un == ln + 2);
+ /* the high un-ln limbs of u will overlap the low part of {x+ln,xn},
+ we need to add or subtract the overlapping part {u + ln, un - ln} */
++ /* Warning! th may be 0, in which case the mpn_add_1 and mpn_sub_1
++ below (with size = th) mustn't be used. In such a case, the limb
++ (carry) will be 0, so that this is semantically a no-op, but if
++ mpn_add_1 and mpn_sub_1 are used, GMP (currently) still does a
++ non-atomic read/write in a place that is not always allocated,
++ with the possible consequences: a crash if the corresponding
++ address is not mapped, or (rather unlikely) memory corruption
++ if another process/thread writes at the same place; things may
++ be worse with future GMP versions. Hence the tests carry != 0. */
+ if (neg == 0)
+ {
+ if (ln > 0)
+ MPN_COPY (x, u, ln);
+ cy = mpn_add (x + ln, x + ln, xn, u + ln, un - ln);
+ /* add cu at x+un */
+- cy += mpn_add_1 (x + un, x + un, th, cu);
++ if (cu != 0)
++ {
++ MPFR_ASSERTD (th != 0);
++ cy += mpn_add_1 (x + un, x + un, th, cu);
++ }
+ }
+ else /* negative case */
+ {
+ /* subtract {u+ln, un-ln} from {x+ln,un} */
+ cy = mpn_sub (x + ln, x + ln, xn, u + ln, un - ln);
+ /* carry cy is at x+un, like cu */
+- cy = mpn_sub_1 (x + un, x + un, th, cy + cu); /* n - un = th */
++ if (cy + cu != 0)
++ {
++ MPFR_ASSERTD (th != 0);
++ cy = mpn_sub_1 (x + un, x + un, th, cy + cu); /* n - un = th */
++ }
+ /* cy cannot be zero, since the most significant bit of Xh is 1,
+ and the correction is bounded by 2^{-h+3} */
+ MPFR_ASSERTD(cy == 0);
+diff -Naurd mpfr-3.0.1-a/version.c mpfr-3.0.1-b/version.c
+--- mpfr-3.0.1-a/version.c 2011-04-12 10:50:02.000000000 +0000
++++ mpfr-3.0.1-b/version.c 2011-05-04 11:18:33.000000000 +0000
+@@ -25,5 +25,5 @@
+ const char *
+ mpfr_get_version (void)
+ {
+- return "3.0.1-p1";
++ return "3.0.1-p2";
+ }