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-rw-r--r--patches/glibc/2.19/102-fix-signed-shift-overlow.patch98
1 files changed, 98 insertions, 0 deletions
diff --git a/patches/glibc/2.19/102-fix-signed-shift-overlow.patch b/patches/glibc/2.19/102-fix-signed-shift-overlow.patch
new file mode 100644
index 0000000..ef49f83
--- /dev/null
+++ b/patches/glibc/2.19/102-fix-signed-shift-overlow.patch
@@ -0,0 +1,98 @@
+commit 5542236837c5c41435f8282ec92799f480c36f18
+Author: Paul Eggert <eggert@cs.ucla.edu>
+Date: Tue Jul 21 22:50:29 2015 -0700
+
+ Port the 0x7efe...feff pattern to GCC 6.
+
+ See Steve Ellcey's bug report in:
+ https://sourceware.org/ml/libc-alpha/2015-07/msg00673.html
+ * string/memrchr.c (MEMRCHR):
+ * string/rawmemchr.c (RAWMEMCHR):
+ * string/strchr.c (strchr):
+ * string/strchrnul.c (STRCHRNUL):
+ Rewrite code to avoid issues with signed shift overflow.
+
+diff --git a/string/memrchr.c b/string/memrchr.c
+index 0c8fd84..86cd5b9 100644
+--- a/string/memrchr.c
++++ b/string/memrchr.c
+@@ -96,15 +96,8 @@ MEMRCHR
+
+ The 1-bits make sure that carries propagate to the next 0-bit.
+ The 0-bits provide holes for carries to fall into. */
+-
+- if (sizeof (longword) != 4 && sizeof (longword) != 8)
+- abort ();
+-
+-#if LONG_MAX <= LONG_MAX_32_BITS
+- magic_bits = 0x7efefeff;
+-#else
+- magic_bits = ((unsigned long int) 0x7efefefe << 32) | 0xfefefeff;
+-#endif
++ magic_bits = -1;
++ magic_bits = magic_bits / 0xff * 0xfe << 1 >> 1 | 1;
+
+ /* Set up a longword, each of whose bytes is C. */
+ charmask = c | (c << 8);
+diff --git a/string/rawmemchr.c b/string/rawmemchr.c
+index 05b22be..228ca9d 100644
+--- a/string/rawmemchr.c
++++ b/string/rawmemchr.c
+@@ -86,15 +86,8 @@ RAWMEMCHR (s, c_in)
+
+ The 1-bits make sure that carries propagate to the next 0-bit.
+ The 0-bits provide holes for carries to fall into. */
+-
+- if (sizeof (longword) != 4 && sizeof (longword) != 8)
+- abort ();
+-
+-#if LONG_MAX <= LONG_MAX_32_BITS
+- magic_bits = 0x7efefeff;
+-#else
+- magic_bits = ((unsigned long int) 0x7efefefe << 32) | 0xfefefeff;
+-#endif
++ magic_bits = -1;
++ magic_bits = magic_bits / 0xff * 0xfe << 1 >> 1 | 1;
+
+ /* Set up a longword, each of whose bytes is C. */
+ charmask = c | (c << 8);
+diff --git a/string/strchr.c b/string/strchr.c
+index 5f90075..f13b2b3 100644
+--- a/string/strchr.c
++++ b/string/strchr.c
+@@ -60,13 +60,8 @@ strchr (const char *s, int c_in)
+
+ The 1-bits make sure that carries propagate to the next 0-bit.
+ The 0-bits provide holes for carries to fall into. */
+- switch (sizeof (longword))
+- {
+- case 4: magic_bits = 0x7efefeffL; break;
+- case 8: magic_bits = ((0x7efefefeL << 16) << 16) | 0xfefefeffL; break;
+- default:
+- abort ();
+- }
++ magic_bits = -1;
++ magic_bits = magic_bits / 0xff * 0xfe << 1 >> 1 | 1;
+
+ /* Set up a longword, each of whose bytes is C. */
+ charmask = c | (c << 8);
+diff --git a/string/strchrnul.c b/string/strchrnul.c
+index 2678f1d..daf0b3f 100644
+--- a/string/strchrnul.c
++++ b/string/strchrnul.c
+@@ -66,13 +66,8 @@ STRCHRNUL (s, c_in)
+
+ The 1-bits make sure that carries propagate to the next 0-bit.
+ The 0-bits provide holes for carries to fall into. */
+- switch (sizeof (longword))
+- {
+- case 4: magic_bits = 0x7efefeffL; break;
+- case 8: magic_bits = ((0x7efefefeL << 16) << 16) | 0xfefefeffL; break;
+- default:
+- abort ();
+- }
++ magic_bits = -1;
++ magic_bits = magic_bits / 0xff * 0xfe << 1 >> 1 | 1;
+
+ /* Set up a longword, each of whose bytes is C. */
+ charmask = c | (c << 8);