breakpad: fix unittest failure when building with clang.

breakpad: fix unittest failure when building with clang.

In C/C++, the result of signed integer overflow is undefined.

The expression "base + size - 1" is parsed as "(base + size) - 1", and
"base + size" can overflow even if "base + (size - 1)" <= INT_MAX.

See http://g/c-compiler-chrome/461JohPKakE/JI3rEBg6FwAJ for more.

BUG=None
TEST='CC=clang CXX=clang++ ./configure && make check'
R=vapier@chromium.org

Committed: https://chromium.googlesource.com/breakpad/breakpad/+/fc134c412a724052188913de6eac99537eb97116

[rahulchaudhry, 2016-01-15 18:22:01]

rahulchaudhry@chromium.org changed reviewers:
+ vapier@chromium.org

[vapier, 2016-01-15 18:29:08]

lgtm

[vapier, 2016-01-15 18:29:36]

Description was changed from

==========
breakpad: fix unittest failure when building with clang.

In C/C++, the result of signed integer overflow is undefined.

The expression "base + size - 1" is parsed as "(base + size) - 1", and
"base + size" can overflow even if "base + (size - 1)" <= INT_MAX.

See http://g/c-compiler-chrome/461JohPKakE/JI3rEBg6FwAJ for more.

BUG=None
TEST='CC=clang CXX=clang++ ./configure && make check'
==========

to

==========
breakpad: fix unittest failure when building with clang.

In C/C++, the result of signed integer overflow is undefined.

The expression "base + size - 1" is parsed as "(base + size) - 1", and
"base + size" can overflow even if "base + (size - 1)" <= INT_MAX.

See http://g/c-compiler-chrome/461JohPKakE/JI3rEBg6FwAJ for more.

BUG=None
TEST='CC=clang CXX=clang++ ./configure && make check'
R=vapier@chromium.org

Committed:
https://chromium.googlesource.com/breakpad/breakpad/+/fc134c412a724052188913d...
==========

[vapier, 2016-01-15 18:29:37]

Committed patchset #1 (id:1) manually as
fc134c412a724052188913de6eac99537eb97116 (presubmit successful).