NaCl docs: mention static libraries for SJLJ

NaCl docs: mention static libraries for SJLJ

This recently came up on our mailing list, and isn't quite obvious.

R=sbc@chromium.org
BUG= none

Committed: https://chromium.googlesource.com/chromium/src/+/5cee41ecd4557e31755e18773b6006052f83a779

[Mark Seaborn, 2015-02-18 18:00:09]

https://codereview.chromium.org/940503003/diff/1/native_client_sdk/src/doc/re...
File native_client_sdk/src/doc/reference/pnacl-c-cpp-language-support.rst
(right):

https://codereview.chromium.org/940503003/diff/1/native_client_sdk/src/doc/re...
native_client_sdk/src/doc/reference/pnacl-c-cpp-language-support.rst:187: to
make sure you rebuild these libraries with exception handling
How does a developer do that?

Isn't -fexceptions the default when compiling C++?

[JF, 2015-02-18 18:19:15]

https://codereview.chromium.org/940503003/diff/1/native_client_sdk/src/doc/re...
File native_client_sdk/src/doc/reference/pnacl-c-cpp-language-support.rst
(right):

https://codereview.chromium.org/940503003/diff/1/native_client_sdk/src/doc/re...
native_client_sdk/src/doc/reference/pnacl-c-cpp-language-support.rst:187: to
make sure you rebuild these libraries with exception handling
On 2015/02/18 18:00:08, Mark Seaborn wrote:
> How does a developer do that?

What do you mean? There are instructions on this above, how would you suggest
improving them?

> Isn't -fexceptions the default when compiling C++?

Yes, it's implied above when -fno-exceptions is mentioned. Do you suggest saying
-fexceptions is the default?

[Mark Seaborn, 2015-02-18 18:36:03]

mseaborn@chromium.org changed reviewers:
+ mseaborn@chromium.org

[Mark Seaborn, 2015-02-18 18:36:03]

https://codereview.chromium.org/940503003/diff/1/native_client_sdk/src/doc/re...
File native_client_sdk/src/doc/reference/pnacl-c-cpp-language-support.rst
(right):

https://codereview.chromium.org/940503003/diff/1/native_client_sdk/src/doc/re...
native_client_sdk/src/doc/reference/pnacl-c-cpp-language-support.rst:187: to
make sure you rebuild these libraries with exception handling
On 2015/02/18 18:19:14, JF wrote:
> On 2015/02/18 18:00:08, Mark Seaborn wrote:
> > How does a developer do that?
> 
> What do you mean? There are instructions on this above, how would you suggest
> improving them?

Sorry, I didn't look at all of the context.

Saying "rebuild" here suggests that nacl-ports uses -fno-exceptions by default. 
Is that the case?

If not, maybe say "...make sure these libraries are not being built with
-fno-exceptions"?

[JF, 2015-02-18 18:43:28]

https://codereview.chromium.org/940503003/diff/1/native_client_sdk/src/doc/re...
File native_client_sdk/src/doc/reference/pnacl-c-cpp-language-support.rst
(right):

https://codereview.chromium.org/940503003/diff/1/native_client_sdk/src/doc/re...
native_client_sdk/src/doc/reference/pnacl-c-cpp-language-support.rst:187: to
make sure you rebuild these libraries with exception handling
On 2015/02/18 18:36:03, Mark Seaborn wrote:
> On 2015/02/18 18:19:14, JF wrote:
> > On 2015/02/18 18:00:08, Mark Seaborn wrote:
> > > How does a developer do that?
> > 
> > What do you mean? There are instructions on this above, how would you
suggest
> > improving them?
> 
> Sorry, I didn't look at all of the context.
> 
> Saying "rebuild" here suggests that nacl-ports uses -fno-exceptions by
default. 
> Is that the case?
> 
> If not, maybe say "...make sure these libraries are not being built with
> -fno-exceptions"?

I clarified a few things, PTAL.

[JF, 2015-02-19 17:36:32]

Ping?

[Mark Seaborn, 2015-02-19 18:22:12]

On 2015/02/19 17:36:32, JF wrote:
> Ping?

Are you pinging me or Sam?

[JF, 2015-02-19 18:33:22]

On 2015/02/19 18:22:12, Mark Seaborn wrote:
> On 2015/02/19 17:36:32, JF wrote:
> > Ping?
> 
> Are you pinging me or Sam?

Both, since you seem interested in this particular docs and Sam was discussing
this topic on the mailing list.

[Sam Clegg, 2015-02-19 18:37:47]

https://codereview.chromium.org/940503003/diff/40001/native_client_sdk/src/do...
File native_client_sdk/src/doc/reference/pnacl-c-cpp-language-support.rst
(right):

https://codereview.chromium.org/940503003/diff/40001/native_client_sdk/src/do...
native_client_sdk/src/doc/reference/pnacl-c-cpp-language-support.rst:180: flag
(set with ``LDFLAGS`` when using Make). Exceptions are disabled by default
Is it a linker flag?  I assumed it was a compiler flag.  If its a linker flag
there is no need to rebuild the libraries (maybe for glibc which uses shared
libraries).

[JF, 2015-02-19 19:15:46]

https://codereview.chromium.org/940503003/diff/40001/native_client_sdk/src/do...
File native_client_sdk/src/doc/reference/pnacl-c-cpp-language-support.rst
(right):

https://codereview.chromium.org/940503003/diff/40001/native_client_sdk/src/do...
native_client_sdk/src/doc/reference/pnacl-c-cpp-language-support.rst:180: flag
(set with ``LDFLAGS`` when using Make). Exceptions are disabled by default
On 2015/02/19 18:37:47, Sam Clegg wrote:
> Is it a linker flag?  I assumed it was a compiler flag.  If its a linker flag
> there is no need to rebuild the libraries (maybe for glibc which uses shared
> libraries).

That's entirely true! Docs updated, thanks for catching this.

[Sam Clegg, 2015-02-19 19:20:55]

lgtm, although now I'm not sure my advice on the list was correct.  If there is
no need to recompile the libs.. i don't know why he try/catch isn't working.

[JF, 2015-02-19 19:22:15]

On 2015/02/19 19:20:55, Sam Clegg wrote:
> lgtm, although now I'm not sure my advice on the list was correct.  If there
is
> no need to recompile the libs.. i don't know why he try/catch isn't working.

I asked for more repro info twice and didn't get an answer... It could be
anything :-)

[commit-bot: I haz the power, 2015-02-19 19:58:37]

Patchset 4 (id:??) landed as
https://crrev.com/5cee41ecd4557e31755e18773b6006052f83a779
Cr-Commit-Position: refs/heads/master@{#317114}

[JF, 2015-02-19 19:58:44]

Committed patchset #4 (id:60001) manually as
5cee41ecd4557e31755e18773b6006052f83a779 (presubmit successful).