From: Martin Sebor <msebor@redhat.com>
Date: Thu, 17 Jan 2019 22:52:47 +0000 (+0000)
Subject: PR middle-end/88273 - [8/9 Regression] warning: 'memcpy' offset [-527, -529]
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=77efc5c25c487ce50ff94bdee7494c6a87fda4f1;p=gcc.git

PR middle-end/88273 - [8/9 Regression] warning: 'memcpy' offset [-527, -529]

PR middle-end/88273 - [8/9 Regression] warning: 'memcpy' offset [-527, -529]
is out of the bounds [0, 16]

gcc/ChangeLog:

	PR middle-end/88273
	* gimple-ssa-warn-restrict.c (builtin_memref::extend_offset_range):
	Handle anti-ranges the same as no range at all.

gcc/testsuite/ChangeLog:

	PR middle-end/88273
	* gcc.dg/Warray-bounds-38.c: New test.

From-SVN: r268048
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index b3649d1e6a6..32b153a8ad6 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2019-01-17  Martin Sebor  <msebor@redhat.com>
+
+	PR middle-end/88273
+	* gimple-ssa-warn-restrict.c (builtin_memref::extend_offset_range):
+	Handle anti-ranges the same as no range at all.
+
 2018-01-17  Steve Ellcey  <sellcey@cavium.com>
 
 	* config/aarch64/aarch64.c (cgraph.h): New include.
diff --git a/gcc/gimple-ssa-warn-restrict.c b/gcc/gimple-ssa-warn-restrict.c
index 42c87190dd8..b069f3aebe6 100644
--- a/gcc/gimple-ssa-warn-restrict.c
+++ b/gcc/gimple-ssa-warn-restrict.c
@@ -319,13 +319,9 @@ builtin_memref::extend_offset_range (tree offset)
 	  offrange[0] += offset_int::from (min, SIGNED);
 	  offrange[1] += offset_int::from (max, SIGNED);
 	}
-      else if (rng == VR_ANTI_RANGE)
-	{
-	  offrange[0] += offset_int::from (max + 1, SIGNED);
-	  offrange[1] += offset_int::from (min - 1, SIGNED);
-	}
       else
 	{
+	  /* Handle an anti-range the same as no range at all.  */
 	  gimple *stmt = SSA_NAME_DEF_STMT (offset);
 	  tree type;
 	  if (is_gimple_assign (stmt)
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 84cb714a148..790556f169a 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2019-01-17  Martin Sebor  <msebor@redhat.com>
+
+	PR middle-end/88273
+	* gcc.dg/Warray-bounds-38.c: New test.
+
 2018-01-17  Steve Ellcey  <sellcey@cavium.com>
 
 	* c-c++-common/gomp/pr60823-1.c: Add aarch64 specific
diff --git a/gcc/testsuite/gcc.dg/Warray-bounds-38.c b/gcc/testsuite/gcc.dg/Warray-bounds-38.c
new file mode 100644
index 00000000000..c9aa0eb8175
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/Warray-bounds-38.c
@@ -0,0 +1,30 @@
+/* PR middle-end/88273 - bogus warning: 'memcpy' offset [-527, -529]
+   is out of the bounds [0, 16]
+   { dg-do compile }
+   { dg-options "-O2 -Wall" }  */
+
+typedef __SIZE_TYPE__ size_t;
+
+void *q;
+
+size_t x, y;
+
+inline void f (char *p, int i, size_t j)
+{
+  size_t n = y ? y : j;
+
+  p += x - i;
+
+  __builtin_memcpy (q, p, n);   /* { dg-bogus "bounds" } */
+
+  x = n;
+}
+
+void g (void)
+{
+  struct { char a[16]; } s;
+
+  f (q, 0, sizeof s);
+
+  f (s.a, 33 * sizeof s, 1);
+}