Add compiler flags that prevent text relocations.

Add compiler flags that prevent text relocations.

Text relocations are a minor security risk. Add compiler flags
that prevent them from reappearing in Android binary.
All existing occurences have been removed after
http://crrev.com/17714003.

TEST=Compile.
BUG=b/8061013

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=209885

[shashi, 2013-07-02 00:23:08]

I have excluded x86 due to performance concerns on x86. Currently x86 binary is
PIC code but in future this could change.

[shashi, 2013-07-02 00:33:08]

On 2013/07/02 00:23:08, shashi wrote:
> I have excluded x86 due to performance concerns on x86. Currently x86 binary
is
> PIC code but in future this could change.

Uploaded the wrong patch, uploading again.

[Yaron, 2013-07-02 00:47:38]

Is there an associated bug?

[shashi, 2013-07-02 00:50:08]

On 2013/07/02 00:47:38, Yaron wrote:
> Is there an associated bug?

Added link to the bug.

[Yaron, 2013-07-02 00:56:06]

https://chromiumcodereview.appspot.com/17820002/diff/21001/chrome/chrome_andr...
File chrome/chrome_android.gypi (right):

https://chromiumcodereview.appspot.com/17820002/diff/21001/chrome/chrome_andr...
chrome/chrome_android.gypi:54: '-Wl,--fatal-warnings',
Should be put this instead near werror in build/common.gypi? Actualy, why aren't
both definitions just in the general build/common.gypi so they apply to all
targets? Also, I don't see any other ports using this flag so I wonder if there
are some warnings perhaps while building official

[shashi, 2013-07-02 01:01:20]

On 2013/07/02 00:56:06, Yaron wrote:
>
https://chromiumcodereview.appspot.com/17820002/diff/21001/chrome/chrome_andr...
> File chrome/chrome_android.gypi (right):
> 
>
https://chromiumcodereview.appspot.com/17820002/diff/21001/chrome/chrome_andr...
> chrome/chrome_android.gypi:54: '-Wl,--fatal-warnings',
> Should be put this instead near werror in build/common.gypi? Actualy, why
aren't
> both definitions just in the general build/common.gypi so they apply to all
> targets? Also, I don't see any other ports using this flag so I wonder if
there
> are some warnings perhaps while building official

I tried that in patchset #1 and libsandbox_linux_jni_unittests.so has non PIC
code that originates from assembly code in sandbox/linux/seccomp-bpf/syscall.cc.
This just prevents text relocation sections from appearing in ContentShell and
ChromiumTestShell.

[Yaron, 2013-07-02 01:30:04]

So rather than sprinkling throughout, I'd prefer you disable it in that one
target. Or put another way: it sounds like in general we don't want PIC code and
that the test is an exception.

[shashi, 2013-07-02 05:07:45]

PTAL, modified to exclude sanbox jni tests. I did not do this initially because
I was afraid that failing on link warnings for tests could introduce more build
failures for Android

[Yaron, 2013-07-02 18:08:13]

https://chromiumcodereview.appspot.com/17820002/diff/49001/build/common.gypi
File build/common.gypi (right):

https://chromiumcodereview.appspot.com/17820002/diff/49001/build/common.gypi#...
build/common.gypi:2747: 'Debug_Base': {
We want this for release too, right?

[shashi, 2013-07-02 18:17:38]

https://chromiumcodereview.appspot.com/17820002/diff/49001/build/common.gypi
File build/common.gypi (right):

https://chromiumcodereview.appspot.com/17820002/diff/49001/build/common.gypi#...
build/common.gypi:2747: 'Debug_Base': {
On 2013/07/02 18:08:13, Yaron wrote:
> We want this for release too, right?

Good catch, right it should be for release too.

[Yaron, 2013-07-02 18:26:09]

lgtm

[commit-bot: I haz the power, 2013-07-02 18:35:06]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/[email protected]/17820002/59001

[commit-bot: I haz the power, 2013-07-02 19:15:42]

Retried try job too often on chromium_presubmit for step(s) presubmit
http://build.chromium.org/p/tryserver.chromium/buildstatus?builder=chromium_p...

[shashi, 2013-07-02 19:18:20]

+jln: owner

[jln (very slow on Chromium), 2013-07-02 20:13:12]

On 2013/07/02 19:18:20, shashi wrote:
> +jln: owner

lgtm

[commit-bot: I haz the power, 2013-07-02 20:15:52]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/[email protected]/17820002/59001

[commit-bot: I haz the power, 2013-07-03 04:32:54]

Change committed as 209885