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<?php
/*******************************************************************************
* Copyright (c) 2015 Eclipse Foundation and others.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://eclipse.org/legal/epl-v10.html
*
* Contributors:
* Eric Poirier (Eclipse Foundation) - Initial implementation
*******************************************************************************/
?>
<h1 class="article-title"><?php echo $pageTitle; ?></h1>
<p>CDT allows for comfortable environment with code highlighting,
navigation, content assist and static analysis. However, most C/C++
projects have to be configured to enjoy those features. Most real
life C/C++ projects heavily depend on code outside of the project
itself, such as system headers or third party libraries. CDT indexer
needs to process those to provide accurate index. Failure to set up
these important settings assuredly will cause the assist tools
misbehave.</p>
<p>
CDT will try to discover include paths and preprocessor symbols
automatically for supported tool chains. This process is known as <a
href="http://help.eclipse.org/kepler/index.jsp?topic=%2Forg.eclipse.cdt.doc.user%2Fconcepts%2Fcdt_c_scanner_discovery.htm">Scanner
Discovery</a> or <b>Autodiscovery</b>. This discovery of symbols
is twofold. One way, CDT will try to detect built-in compiler
symbols and include paths running the compiler with special options
and parse the output. Another method that CDT employs is to analyze
build output of the regular build with Build Output Parser. Often,
include paths are supplied to the compiler with -I options, and
macros with -D options. That relies on verbose build output of your
build where all these options are actually printed by make.
</p>
<p>
<a
href="http://help.eclipse.org/kepler/index.jsp?topic=%2Forg.eclipse.cdt.doc.user%2Fconcepts%2Fcdt_c_scanner_discovery.htm">Scanner
Discovery</a> uses <b>Language Settings Providers</b> to find
include paths and preprocessor symbols. Language Settings Providers
can be configured on project properties page "Preprocessor Include
Paths, Macros, etc.", <a
href="http://help.eclipse.org/kepler/index.jsp?topic=%2Forg.eclipse.cdt.doc.user%2Freference%2Fcdt_u_prop_general_sd_providers.htm">Providers
tab</a> for a configuration and on preference page <a
href="http://help.eclipse.org/kepler/index.jsp?topic=%2Forg.eclipse.cdt.doc.user%2Freference%2Fcdt_u_pref_build_scanner_discovery.htm">C/C++
Preferences: Scanner Discovery</a> for shared providers.
</p>
<p>
If information retrieved by auto-discovery is insufficient or the
project deviates from a standard one supported by CDT a user can
inspect discovered entries and enter additional include paths and
macros manually on the property page "Preprocessor Include Paths,
Macros, etc.", <a
href="http://help.eclipse.org/kepler/index.jsp?topic=%2Forg.eclipse.cdt.doc.user%2Freference%2Fcdt_u_prop_general_sd_entries.htm">Entries
tab</a>.
</p>
<p>
There are other ways to make C/C++ indexer aware of include paths or
macros. One way is to set up them in MBS via "Paths and Symbols"
project properties. See <a
href="http://help.eclipse.org/kepler/index.jsp?topic=%2Forg.eclipse.cdt.doc.user%2Ftasks%2Fcdt_t_proj_paths.htm">Including
paths and symbols in Managed Build System</a>. These entries are
supplied to the indexer with MBS Language Settings Provider.
</p>
<h2>Scanner Discovery</h2>
<h3>General</h3>
<p>
<b>Scanner Discovery</b> (sometimes called <b>Autodiscovery</b>) is
a method of finding include paths and predefined preprocessor macros
which the compiler uses during compilation of the code.
</p>
<p>Even a simplest C/C++ program just printing "Hello World" needs to
include system headers. Consider:</p>
<pre class="prettyprint lang-xtend">
#include &lt;stdio.h&gt;
#include &lt;stdlib.h&gt;
int main(void) {
puts("!!!Hello World!!!");
return EXIT_SUCCESS;
}
</pre>
<br />
<p>
Indexer needs to be able to find headers <i>stdio.h</i> and <i>stdlib.h</i>
and parse them to provide accurate index. In this example, the
headers define prototype of function <i>puts</i> and macro <i>EXIT_SUCCESS</i>.
</p>
<p>CDT will try to discover include paths and preprocessor symbols
automatically for supported tool chains. There are 2 main ways to
discover those:</p>
<ol>
<li><b>Built-in</b> Settings. CDT will try to detect built-in
compiler symbols and include paths running the compiler with
special options and parse the output of this special run. Most
compilers provide such an option to print built-in include paths
and symbols. Built-in settings are implied and do not get passed
to compiler during regular compilation.</li>
<li><b>Build Output Parser (BOP)</b>. Another method that CDT
employs is to analyze build output of the regular build with Build
Output Parser. Often, include paths are supplied to the compiler
with <i>-I</i> options, and macros with <i>-D</i> options and BOP
will try to find those in the output. That method relies on
verbose build output of your build where all these options are
actually printed by make.</li>
</ol>
<p>
CDT uses <b>Language Settings Providers</b> to discover the settings
(starting with version CDT 8.1). Typically Language settings
Providers are specialized. One will provide built-in compiler
settings and another one settings detected by Build output Parser.
There is also an extension point defined in CDT to allow third party
Eclipse plugins to contribute custom Language Settings Providers.
</p>
<p>The setting entries found by Scanner Discovery can be inspected in
project properties on "Preprocessor Include Paths, Macros etc."
page. Each Language Settings Provider can be expanded to show the
entries it discovered.</p>
<img
src="/community/eclipse_newsletter/2013/october/images/octarticle4.1.png"
alt="prop entries" width="600" />
<br />
<br />
<p>If information retrieved by auto-discovery is insufficient or the
project deviates from a standard one supported by CDT a user can
enter additional include paths and macros manually under "User
Settings Entries".</p>
<h3>Project Explorer View</h3>
<p>
The <b>Project Explorer View</b> provides a means to view some of
the settings. The discovered include paths are shown under the
project when "Includes" node is expanded.
</p>
<p>
Also, a <b>"Wrench" overlay</b> icon is shown for those file/folders
where distinct entries are discovered which differ from those of
parent folder. Wrench is not shown on project level.
</p>
<p>
In the example below, <i>Hello.cpp</i> was compiled with added <i>-DHELLO</i>
compiler option. After BOP discovery "Wrench" overlay is shown for
this file.
</p>
<img
src="/community/eclipse_newsletter/2013/october/images/octarticle4.2.png"
alt="project explorer" width="600" />
<br />
<br />
<h3>Console View</h3>
<p>The output of built-in compiler specs detectors can be inspected to
troubleshoot problems running the command. To do so, enable checkbox
"Allocate console in the Console View".</p>
<img
src="/community/eclipse_newsletter/2013/october/images/octarticle4.3.png"
alt="specs detector options" width="600" />
<br />
<br />
<p>When checkbox "Allocate console in the Console View" is enabled,
output of each run of the provider will be directed to a special
console in the Console View.</p>
<img
src="/community/eclipse_newsletter/2013/october/images/octarticle4.4.png"
alt="sd console view" width="600" />
<br />
<br />
<h2>C/C++ Project properties: Preprocessor Include Paths, Macros, etc.</h2>
<p>
Include paths and preprocessor macros for C/C++ indexer and other <b>Language
Settings</b> are supplied by <b>Language Settings Providers</b>
using <a
href="http://help.eclipse.org/kepler/index.jsp?topic=%2Forg.eclipse.cdt.doc.user%2Fconcepts%2Fcdt_c_scanner_discovery.htm">Scanner
Discovery</a> mechanism.
</p>
<p>
The entries can be inspected and set up on project properties page
"Preprocessor Include Paths, Macros, etc." - <a
href="http://help.eclipse.org/kepler/index.jsp?topic=%2Forg.eclipse.cdt.doc.user%2Freference%2Fcdt_u_prop_general_sd_entries.htm">Entries
tab</a>.
</p>
<p>
Language Settings Providers can be set up and configured for the
selected configuration on project properties page "Preprocessor
Include Paths, Macros, etc." - <a
href="http://help.eclipse.org/kepler/index.jsp?topic=%2Forg.eclipse.cdt.doc.user%2Freference%2Fcdt_u_prop_general_sd_providers.htm">Providers
tab</a>.
</p>
<h2>C/C++ Project properties: Preprocessor Include Paths, Macros, etc.
- Entries tab</h2>
<p>
Include paths and preprocessor macros for C/C++ indexer can be
inspected and set up on the project property page "Preprocessor
Include Paths, Macros, etc.", "Entries" tab. This tab presents <b>Language
Settings Providers</b> employed by <a
href="http://help.eclipse.org/kepler/index.jsp?topic=%2Forg.eclipse.cdt.doc.user%2Fconcepts%2Fcdt_c_scanner_discovery.htm">Scanner
Discovery</a> to provide include paths, macros and other <b>Language
Settings</b>.
</p>
<p>Note that the entries could be set also on an individual resource,
such as file or folder. Open file or folder properties to inspect
resource-specific entries. The entries on a folder or a project will
apply to all subfolders and C/C++ files under it - unless overridden
on a lower level.</p>
<p>"Entries" tab shows a list of Language Settings Providers for each
language. A provider node can be expanded to show include paths and
macros defined by the provider. A user can add custom entries here
under "User Setting Entries" provider.</p>
<img
src="/community/eclipse_newsletter/2013/october/images/octarticle4.1.png"
alt="sd console view" width="600" />
<br />
<br />
<h4>Entries tab controls</h4>
<table style="border: 1px solid black;">
<thead>
<tr>
<th style="border: 1px solid black;"><b>Group</b></th>
<th style="border: 1px solid black;"><b>Description</b></th>
</tr>
</thead>
<tbody>
<tr style="border: 1px solid black;">
<td style="border: 1px solid black;"><b>Configuration</b></td>
<td style="border: 1px solid black;"><a
href="http://help.eclipse.org/kepler/index.jsp?topic=%2Forg.eclipse.cdt.doc.user%2Freference%2Fcdt_u_prop_all.htm">Click
here for a description</a></td>
</tr>
<tr style="border: 1px solid black;">
<td style="border: 1px solid black;"><b>Manage Configurations...</b></td>
<td style="border: 1px solid black;"><a
href="http://help.eclipse.org/kepler/index.jsp?topic=%2Forg.eclipse.cdt.doc.user%2Freference%2Fcdt_u_prop_all.htm">Click
here for a description</a></td>
</tr>
<tr style="border: 1px solid black;">
<td style="border: 1px solid black;"><b>Languages</b></td>
<td style="border: 1px solid black;">Lists all of the languages
defined by the tool chain. Select a language to see the list
of applicable providers.</td>
</tr>
<tr style="border: 1px solid black;">
<td style="border: 1px solid black;"><b>Setting Entries</b></td>
<td style="border: 1px solid black;">Lists all of the providers
for the selected language and entries supplied by them. Expand
a provider node to see the entries.</td>
</tr>
<tr style="border: 1px solid black;">
<td style="border: 1px solid black;"><b>Show built-in values</b></td>
<td style="border: 1px solid black;">Disable checkbox "Show
built-in values" to filter out built-in setting entries in the
view. Built-in compiler entries need to be provided to C/C++
indexer but not to the compiler during the build.</td>
</tr>
<tr style="border: 1px solid black;">
<td style="border: 1px solid black;"><b>Add...</b></td>
<td style="border: 1px solid black;">Add an entry to the
provider. Enabled only when the provider supports the
operation.</td>
</tr>
<tr style="border: 1px solid black;">
<td style="border: 1px solid black;"><b>Edit...</b></td>
<td style="border: 1px solid black;">Edit the selected settings
entry. Enabled only when the provider supports the operation.</td>
</tr>
<tr style="border: 1px solid black;">
<td style="border: 1px solid black;"><b>Delete</b></td>
<td style="border: 1px solid black;">Delete the selected
settings entry. Enabled only when the provider supports the
operation.</td>
</tr>
<tr style="border: 1px solid black;">
<td style="border: 1px solid black;"><b>Move Up</b></td>
<td style="border: 1px solid black;">Moves the selected entry
higher in the list. Enabled only when the provider supports
the operation.</td>
</tr>
<tr style="border: 1px solid black;">
<td style="border: 1px solid black;"><b>Move Down</b></td>
<td style="border: 1px solid black;">Moves the selected entry
lower in the list. Enabled only when the provider supports the
operation.</td>
</tr>
</tbody>
</table>
<h2>Adding and Editing entries</h2>
<p>
Use <b>Add...</b> and <b>Edit...</b> buttons to add or modify the
entries. Both buttons open similar dialog described here.
</p>
<img
src="/community/eclipse_newsletter/2013/october/images/octarticle4.6.png"
alt="include directory" width="600" />
<br />
<br />
<h4>Add/Edit entries dialog</h4>
<table style="border: 1px solid black;">
<thead>
<tr>
<th style="border: 1px solid black;"><b>Group</b></th>
<th style="border: 1px solid black;"><b>Description</b></th>
</tr>
</thead>
<tbody>
<tr style="border: 1px solid black;">
<td style="border: 1px solid black;"><b>Kind of Setting Entry</b></td>
<td style="border: 1px solid black;"><img
src="/community/eclipse_newsletter/2013/october/images/octarticle4.7.png"
alt="include directory" /><br />A dropbox to select desired
kind of setting entry. This dropbox is not available in "Edit"
mode.</td>
</tr>
<tr style="border: 1px solid black;">
<td style="border: 1px solid black;"><b>Kind of path</b></td>
<td style="border: 1px solid black;"><img
src="/community/eclipse_newsletter/2013/october/images/octarticle4.8.png"
alt="project path" /><br />A dropbox to select desired kind of
path. This dropbox is shown for path entries only.</td>
</tr>
<tr style="border: 1px solid black;">
<td style="border: 1px solid black;"><b>Path</b></td>
<td style="border: 1px solid black;">Enter path value of the
entry.<br> This field is shown for path entries only.
</td>
</tr>
<tr style="border: 1px solid black;">
<td style="border: 1px solid black;"><b>Open folder button</b></td>
<td style="border: 1px solid black;">Use folder button to
navigate folder structure to select existing path. The
provided dialog varies depending on the kind of path selected
in the corresponding dropbox.<br />This button is shown for
path entries only.
</td>
</tr>
<tr style="border: 1px solid black;">
<td style="border: 1px solid black;"><b>Variables</b></td>
<td style="border: 1px solid black;">Select one of the build or
environment variables provided by CDT to embed into "Path"
field.<br />This button is enabled only for File System Paths.
</td>
</tr>
<tr style="border: 1px solid black;">
<td style="border: 1px solid black;"><b>Treat as built-in</b></td>
<td style="border: 1px solid black;">Enable this checkbox to
mark the entry as built-in. Built-in compiler entries need to
be provided to C/C++ indexer but not to the compiler during
the build.</td>
</tr>
<tr style="border: 1px solid black;">
<td style="border: 1px solid black;"><b>Contains system headers</b></td>
<td style="border: 1px solid black;">Enable if the include path
is a system directory which contains system headers.<br />This
checkbox is shown for Include Directories only.
</td>
</tr>
<tr style="border: 1px solid black;">
<td style="border: 1px solid black;"><b>Framework folder</b></td>
<td style="border: 1px solid black;">Mac OS has a unique way of
specifying include directories for Frameworks. Enable if the
included directory is Mac Framework directory.<br />This
checkbox is shown for Include Directories only.
</td>
</tr>
<tr style="border: 1px solid black;">
<td style="border: 1px solid black;"><b>Name</b></td>
<td style="border: 1px solid black;">Shown for Preprocessor
Macro only. Specify the macro name here.</td>
</tr>
<tr style="border: 1px solid black;">
<td style="border: 1px solid black;"><b>Value</b></td>
<td style="border: 1px solid black;">Shown for Preprocessor
Macro only. Specify the macro name here.</td>
</tr>
</tbody>
</table>
<h2>C/C++ Project properties: Preprocessor Include Paths, Macros, etc.
- Providers tab</h2>
<p>
Include paths and preprocessor macros for C/C++ indexer and other <b>Language
Settings</b> are supplied by <b>Language Settings Providers</b> as
part of <a
href="http://help.eclipse.org/kepler/index.jsp?topic=%2Forg.eclipse.cdt.doc.user%2Fconcepts%2Fcdt_c_scanner_discovery.htm">Scanner
Discovery</a>. Language Settings Providers can be set up and
configured for the selected configuration in the "Providers" tab.
</p>
<p>"Providers" tab is only shown in properties of a project, not in
properties of a file or a folder.</p>
<img
src="/community/eclipse_newsletter/2013/october/images/octarticle4.9.png"
alt="preprocessor includes" width="600" />
<br />
<br />
<h4>Providers tab controls</h4>
<table style="border: 1px solid black;">
<thead>
<tr>
<th style="border: 1px solid black;"><b>Group</b></th>
<th style="border: 1px solid black;"><b>Description</b></th>
</tr>
</thead>
<tbody>
<tr style="border: 1px solid black;">
<td style="border: 1px solid black;"><b>Configuration</b></td>
<td style="border: 1px solid black;"><a
href="http://help.eclipse.org/kepler/index.jsp?topic=%2Forg.eclipse.cdt.doc.user%2Freference%2Fcdt_u_prop_all.htm">Click
here for a description</a></td>
</tr>
<tr style="border: 1px solid black;">
<td style="border: 1px solid black;"><b>Manage Configurations...</b></td>
<td style="border: 1px solid black;"><a
href="http://help.eclipse.org/kepler/index.jsp?topic=%2Forg.eclipse.cdt.doc.user%2Freference%2Fcdt_u_prop_all.htm">Click
here for a description</a></td>
</tr>
<tr style="border: 1px solid black;">
<td style="border: 1px solid black;"><b>Language</b></td>
<td style="border: 1px solid black;">Lists all of the providers
available for the current configuration.</td>
</tr>
<tr style="border: 1px solid black;">
<td style="border: 1px solid black;"><b>Setting Providers List</b></td>
<td style="border: 1px solid black;">Select the providers to
assign to the configuration.</td>
</tr>
<tr style="border: 1px solid black;">
<td style="border: 1px solid black;"><b>Clear Entries</b></td>
<td style="border: 1px solid black;">Clears all entries of the
selected provider. This operation takes effect after pressing
"Apply" or "OK". Normally this will trigger a rerun if the
provider supplies built-in compiler settings. Build output
parsers will regain language settings after build while
parsing new build output.<br />This operation might be
unavailable if the provider does not have any language
settings. Some providers may not have the capability to clear.<br />On
this property page, this operation is applicable only to
non-shared providers.
</td>
</tr>
<tr style="border: 1px solid black;">
<td style="border: 1px solid black;"><b>Reset</b></td>
<td style="border: 1px solid black;">Resets options of the
selected provider to default values. This operation also
clears the provider entries. The button can be enabled if some
options in "Language Settings Provider Options" panel were
changed.<br />In this dialog, this operation is applicable
only to non-shared providers.
</td>
</tr>
<tr style="border: 1px solid black;">
<td style="border: 1px solid black;"><b>Move Up</b></td>
<td style="border: 1px solid black;">Moves the selected provider
higher in the list.</td>
</tr>
<tr style="border: 1px solid black;">
<td style="border: 1px solid black;"><b>Move Down</b></td>
<td style="border: 1px solid black;">Moves the selected provider
lower in the list.</td>
</tr>
</tbody>
</table>
<p>
A user can define some options for configuration providers (or
"non-shared") on this property page. Note that providers can be
either shared or defined per configuration. Options of global (or
"shared") providers can be configured on <a
href="http://help.eclipse.org/kepler/index.jsp?topic=%2Forg.eclipse.cdt.doc.user%2Freference%2Fcdt_u_pref_build_scanner_discovery.htm">C/C++
Preferences: Scanner Discovery</a>.
</p>
<p>There are 2 specific options that are added for non-shared
providers defined per configuration. They are described in the table
below.</p>
<h4>Discovery tab</h4>
<table style="border: 1px solid black;">
<thead>
<tr>
<th style="border: 1px solid black;"><b>Group</b></th>
<th style="border: 1px solid black;"><b>Description</b></th>
</tr>
</thead>
<tbody>
<tr style="border: 1px solid black;">
<td style="border: 1px solid black;"><b>Use global provider
shared between projects</b></td>
<td style="border: 1px solid black;">Providers can be global or
belong to a configuration. Global providers share their
entries between all configurations which refer to them.</td>
</tr>
<tr style="border: 1px solid black;">
<td style="border: 1px solid black;"><b>Store entries in project
settings folder</b></td>
<td style="border: 1px solid black;">Providers can persist their
entries in workspace or under project folder. Storing entries
under project when approprate can make sharing with the other
team members easier.</td>
</tr>
</tbody>
</table>
<p>
The rest of the options is described in <a
href="http://help.eclipse.org/kepler/index.jsp?topic=%2Forg.eclipse.cdt.doc.user%2Freference%2Fcdt_u_pref_build_scanner_discovery.htm">C/C++
Preferences: Scanner Discovery</a>, under <b>Language Settings
Providers Options</b>.
</p>
<h2>Scanner Discovery Preferences</h2>
<h3>General</h3>
<p>
Use the <b>Discovery Tab</b> on <img
src="/community/eclipse_newsletter/2013/october/images/octarticle4.12.png" alt="">
<a
href="javascript:executeCommand(%22org.eclipse.ui.window.preferences(preferencePageId=org.eclipse.cdt.ui.preferences.BuildSettingProperties)%22)">Build</a>
preference panel to define global scanner discovery options.
</p>
<p>
In the Discovery tab you can see a list of <b>Language Settings
Providers</b>. Language Settings Providers supply <b>Language
Settings</b> such as include paths and preprocessor macros for the
indexer and other components of CDT.
</p>
<img
src="/community/eclipse_newsletter/2013/october/images/octarticle4.10.png"
alt="preprocessor includes" width="600" />
<br />
<br />
<p>
A user can define some properties for global (or "shared") providers
on this preference. Note that providers can be either shared or
defined per configuration. Properties for non-shared providers can
be defined in <a
href="http://help.eclipse.org/kepler/index.jsp?topic=%2Forg.eclipse.cdt.doc.user%2Freference%2Fcdt_u_prop_general_scanner_discovery.htm">Project
properties: Preprocessor Include Paths, Macros, etc.</a>
</p>
<h4>Discovery tab</h4>
<table style="border: 1px solid black;">
<thead>
<tr>
<th style="border: 1px solid black;"><b>Group</b></th>
<th style="border: 1px solid black;"><b>Description</b></th>
</tr>
</thead>
<tbody>
<tr style="border: 1px solid black;">
<td style="border: 1px solid black;"><b>Language Settings
Providers</b></td>
<td style="border: 1px solid black;">Lists the available
language settings providers.</td>
</tr>
<tr style="border: 1px solid black;">
<td style="border: 1px solid black;"><b>Clear Entries</b></td>
<td style="border: 1px solid black;">Click to clear all entries
of the selected provider. This operation takes effect after
pressing "Apply" or "OK". Normally this will trigger a rerun
if the provider supplies built-in compiler settings. Build
output parsers will regain language settings after build while
parsing new build output. This operation might be unavailable
if the provider does not have any language settings. Some
providers may not have the capability to clear.</td>
</tr>
<tr style="border: 1px solid black;">
<td style="border: 1px solid black;"><b>Reset</b></td>
<td style="border: 1px solid black;">Click to reset options of
the selected provider to default values. This operation also
clears the provider entries. The button can be enabled if some
options in "Language Settings Provider Options" panel were
changed.</td>
</tr>
</tbody>
</table>
<h4>Kinds of Language Settings Providers</h4>
<table style="border: 1px solid black;">
<thead>
<tr>
<th style="border: 1px solid black;"><b>Provider</b></th>
<th style="border: 1px solid black;"><b>Description</b></th>
</tr>
</thead>
<tbody>
<tr style="border: 1px solid black;">
<td style="border: 1px solid black;"><b>Build Output Parser
Provider</b></td>
<td style="border: 1px solid black;">Build Output Parser
Provider parses output of build looking for include paths and
macros passed to the compiler via compiler options. Include
files, macro files passed the the compiler and some other
compiler options are normally also recognized.<br />For gcc,
include paths commonly passed with "-I" option and macros with
"-D" option. The language settings found by BOP are available
after the build is finished.
</td>
</tr>
<tr style="border: 1px solid black;">
<td style="border: 1px solid black;"><b>Built-in Compiler
Settings Provider</b></td>
<td style="border: 1px solid black;">Built-in Compiler Settings
Provider launches the compiler with special options that
instruct the compiler to print built-in settings such as
include paths to internal system headers and the list of
internally predefined macros. This provider is usually shared
between projects in workspace and runs in background once.
When it is finished the language settings are available to all
the projects between which it is shared.</td>
</tr>
<tr style="border: 1px solid black;">
<td style="border: 1px solid black;"><b>Managed Build Language
Settings Provider</b></td>
<td style="border: 1px solid black;">MBS Provider supplies
language settings provided by Managed Build System.</td>
</tr>
<tr style="border: 1px solid black;">
<td style="border: 1px solid black;"><b>User Language Settings
Provider</b></td>
<td style="border: 1px solid black;">A user has an opportunity
to enter language settings manually using this provider. User
Language Settings Provider should be normally the first in the
list so these settings override settings supplied by other
providers.</td>
</tr>
<tr style="border: 1px solid black;">
<td style="border: 1px solid black;"><b>Contributed PathEntry
Containers</b></td>
<td style="border: 1px solid black;">This provider is here for
backward compatibility support of PathEntry Containers from
older versions of CDT. Using this method is not recommended.</td>
</tr>
<tr style="border: 1px solid black;">
<td style="border: 1px solid black;"><b>Contributed ScannerInfo
Entries</b></td>
<td style="border: 1px solid black;">This provider is here for
backward compatibility support of ScannerInfo Entries from
older versions of CDT. Using this method is not recommended.</td>
</tr>
</tbody>
</table>
<h3>Language Settings Providers Options</h3>
<p>Language settings providers can have options that affect the
behavior of a provider. These options are presented in "Language
Settings Provider Options" panel.</p>
<h4>Build Output Parser Options</h4>
<img
src="/community/eclipse_newsletter/2013/october/images/octarticle4.11.png"
alt="settings" width="600" />
<br />
<br />
<h4>Build Output Parser Options</h4>
<table style="border: 1px solid black;">
<thead>
<tr>
<th style="border: 1px solid black;"><b>Provider</b></th>
<th style="border: 1px solid black;"><b>Options</b></th>
</tr>
</thead>
<tbody>
<tr style="border: 1px solid black;">
<td style="border: 1px solid black;"><b>Compiler command pattern</b></td>
<td style="border: 1px solid black;">The pattern which is used
to recognize compiler command in build output.<br />Note that
the pattern is Java regular expression pattern, it is NOT
globing pattern used to expand file name in command line.
</td>
</tr>
<tr style="border: 1px solid black;">
<td style="border: 1px solid black;"><b>Container to keep
discovered entries</b></td>
<td style="border: 1px solid black;">The discovered entries can
be associated with the project, enclosing folder or the file
itself.</td>
</tr>
<tr style="border: 1px solid black;">
<td style="border: 1px solid black;"><b>Use heuristics to
resolve paths</b></td>
<td style="border: 1px solid black;">The provider will try to
find the best match for the discovered path in the project or
workspace trying several heuristics. If disabled, the
discovered paths will stay as they appear in build output.</td>
</tr>
</tbody>
</table>
<h4>Built-in Compiler Settings Provider Options</h4>
<img
src="/community/eclipse_newsletter/2013/october/images/octarticle4.3.png"
alt="settings" width="600" />
<br />
<br />
<h4>Builtin Compiler Settings Provider Options</h4>
<table style="border: 1px solid black;">
<thead>
<tr>
<th style="border: 1px solid black;"><b>Provider</b></th>
<th style="border: 1px solid black;"><b>Options</b></th>
</tr>
</thead>
<tbody>
<tr style="border: 1px solid black;">
<td style="border: 1px solid black;"><b>Command to get compiler
specs</b></td>
<td style="border: 1px solid black;">The command to make the
compiler print built-in settings. Following variables are
recognized:<br />
<ul>
<li>&#36;{COMMAND} - compiler command from the toolchain,
such as "gcc".</li>
<li>&#36;{INPUTS} - indicates normally an empty specs file
required by the compiler. In no such file exists the file
gets created temporarily in Eclipse workspace plugin area.</li>
<li>&#36;{EXT} - an extension for the language to discover
built-in settings. A provider can be associated with
multiple languages and it will run the command for each
language.</li>
</ul>
</td>
</tr>
<tr style="border: 1px solid black;">
<td style="border: 1px solid black;"><b>Browse</b></td>
<td style="border: 1px solid black;">Use this button to locate
the compiler on the file system. The result is put into
"Command to get compiler specs" input field.</td>
</tr>
<tr style="border: 1px solid black;">
<td style="border: 1px solid black;"><b>Allocate console in the
Console View</b></td>
<td style="border: 1px solid black;">Enable to troubleshoot
problems running the command. When enabled, output of each run
of the provider will be directed to a special console in the
Console View. See also <a
href="http://help.eclipse.org/kepler/index.jsp?topic=%2Forg.eclipse.cdt.doc.user%2Fconcepts%2Fcdt_c_scanner_discovery.htm">Scanner
Discovery</a> - Console View.
</td>
</tr>
</tbody>
</table>
<p>
To see the entries a provider discovered, go to project properties
(or the properties of the resource of interest), see <a
href="http://help.eclipse.org/kepler/index.jsp?topic=%2Forg.eclipse.cdt.doc.user%2Freference%2Fcdt_u_prop_general_scanner_discovery.htm">Project
properties: Preprocessor Include Paths, Macros, etc</a>.
</p>
<p>A hint: After compiler upgrade re-discover changed settings with
"Clear Entries" of the appropriate provider.</p>
<h3>References</h3>
<p>
The material provided in this article is also available with Eclipse
Kepler C/C++ Development User Guide in <a
href="http://help.eclipse.org/kepler/index.jsp?topic=%2Forg.eclipse.cdt.doc.user%2Fconcepts%2Fcdt_c_scanner_discovery.htm">Scanner
Discovery</a> section.
</p>
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<div class="bottomitem">
<h3>About the Authors</h3>
<div class="row">
<div class="col-sm-12">
<p class="author-name">
Andrew Gvozdev</p>
</div>
</div>
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