| MATLAB® | |
| On this page… |
|---|
What You Need to Build MEX-Files Selecting a Compiler on Windows Platforms |
You need a compiler and the mex function to build MEX-files. MATLAB software supports many compilers and provides computer configuration files, called options files, designed specifically for these compilers. For an up-to-date list of supported compilers, see Technical Note 1601.
On 32-bit Microsoft Windows platforms, MATLAB provides a C compiler, Lcc. To view Help on using the Lcc compiler, type:
winopen(fullfile(matlabroot, '\sys\lcc\bin\wedit.hlp'))
If you have multiple compilers installed on your system, you can choose which compiler to use, as described in Selecting a Compiler on Windows Platforms or Selecting a Compiler on UNIX Platforms.
To help you configure your system using a sample MEX-file, see Overview of Building the timestwo MEX-File.
If you have difficulty creating MEX-files, see Creating a Source MEX-File, or refer to Troubleshooting MEX-Files.
A selected compiler configuration specifies the compiler and build options MATLAB uses every time you invoke the mex build script. The compiler in this configuration is the selected compiler. It is the program that compiles source code into object code. A configuration is the set of programs and instructions that builds source code into shared libraries and standalone executable files.
To select a configuration, use the mex -setup command. You can set or change the configuration anytime, from either the MATLAB or the system command prompt. After you choose a configuration, it becomes the default and you no longer have to select one to compile MEX-files.
You can view information about the selected compiler configuration using the mex.getCompilerConfigurations function.
You can change the compiler configuration for a single call to the mex script using the -f switch, which specifies an options file. Subsequent calls to mex continue to use the selected compiler configuration.
For more information about these topics, see:
To see the list of supported compilers on the Windows platform, type:
mex -setup
MATLAB displays the following dialog. The text has been formatted to fit the page.
Note The list of compilers shown in your version of MATLAB may be different from the list shown in this example. For an up-to-date list of supported compilers, see Technical Note 1601. |
Please choose your compiler for building external interface (MEX) files: Would you like mex to locate installed compilers [y]/n? N Select a compiler: [1] Intel C++ 9.1 (with Microsoft Visual C++ 2005 linker) [2] Intel Visual Fortran 10.1 (with Microsoft Visual C++ 2005 linker) [3] Intel Visual Fortran 9.1 (with Microsoft Visual C++ 2005 linker) [4] Lcc-win32 C 2.4.1 [5] Microsoft Visual C++ 6.0 [6] Microsoft Visual C++ .NET 2003 [7] Microsoft Visual C++ 2005 [8] Microsoft Visual C++ 2005 Express Edition [9] Microsoft Visual C++ 2008 [10] Open WATCOM C++ [11] Open WATCOM C++ 1.3 [0] None Compiler: 0 Done . . .
MATLAB helps you choose a compiler configuration by generating a list of either:
All supported compilers. This is the same information found in Technical Note 1601. To see this list, follow the instructions in Viewing Supported Windows Compilers.
Installed compilers found on your system. Only compilers supported by MATLAB are in this list.
To select a configuration from a list of supported compilers found on your system, type:
mex -setup
MATLAB displays the following dialog. The text has been formatted to fit the page.
Note The list of compilers shown on your system may be different from the list shown in this example. The path names to your compilers may also be different. For an up-to-date list of supported compilers, see Technical Note 1601. |
Please choose your compiler for building external interface (MEX)
files.
Would you like mex to locate installed compilers [y]/n? y
Select a compiler:
[1] Intel Visual Fortran 9.1 (with Microsoft Visual C++ 2005 linker) in
C:\Program Files\Intel\Compiler\Fortran\9.1
[2] Lcc-win32 C 2.4.1 in C:\PROGRA~1\MATLAB\R2007b\sys\lcc
[3] Microsoft Visual C++ 2005 in
C:\Program Files\Microsoft Visual Studio 8
[0] None
Compiler: 2
Please verify your choices:
Compiler: Lcc-win32 C 2.4.1
Location: C:\PROGRA~1\MATLAB\R2007b\sys\lcc
Are these correct?([y]/n): y
Trying to update options file:
C:\WINNT\Profiles\hhowell\Application Data\MathWorks\MATLAB\R2007b\
mexopts.bat
From template:
C:\PROGRA~1\MATLAB\R2007b\bin\win32\mexopts\lccopts.bat
Done . . .
When to Change the Selected Compiler Configuration. On Windows systems, if you create both C and Fortran MEX-files, you must choose the appropriate compiler for the language you are using. If your selected compiler is the wrong language, it generates error messages. To see the language of your selected compiler, type:
cc = mex.getCompilerConfigurations; cc.Language
You can change the compiler using either mex -setup or by Specifying a Windows Options File.
On Windows systems, there is one compiler configuration. Use the mex.getCompilerConfigurations function to find the selected compiler configuration.
To get information about the selected compiler, type:
cc = mex.getCompilerConfigurations
MATLAB creates a mex.CompilerConfiguration object cc and displays its properties:
cc =
mex.CompilerConfiguration
package: mex
properties:
Name: 'Microsoft Visual C++ 2005'
Manufacturer: 'Microsoft'
Language: 'C++'
Version: '8.0'
Location: 'C:\Program Files\Microsoft Visual Studio 8'
Details: [1x1 mex.CompilerConfigurationDetails]
list of methods
To see the build options used by the selected compiler, type:
ccOptions = cc.Details
MATLAB creates a mex.CompilerConfigurationDetails object ccOptions and displays the options:
ccOptions =
mex.CompilerConfigurationDetails
package: mex
properties:
CompilerExecutable: 'cl'
CompilerFlags: [1x120 char]
OptimizationFlags: '/O2 /Oy- /DNDEBUG'
DebugFlags: '/Zi /Fd"%OUTDIR%%MEX_NAME%%MEX_EXT%.pdb"'
LinkerExecutable: 'link'
LinkerFlags: [1x257 char]
LinkerOptimizationFlags: ''
LinkerDebugFlags: '/DEBUG
/PDB:"%OUTDIR%%MEX_NAME%%MEX_EXT%.pdb"'
list of methodsMATLAB includes template options files you can use with particular compilers. The options files are located in the following directories.
| Platform | Directory |
|---|---|
| Windows | matlabroot\bin\win32\mexopts |
| Windows x64 | matlabroot\bin\win64\mexopts |
On Windows systems, the options file has a .bat file extension.
For information on how to modify options files for particular systems, see Custom Building MEX-Files.
Use the -f option to specify an options file. To use this option, at the MATLAB prompt, type:
mex filename -f optionsfile
where optionsfile is the full path to the options file.
You might need to specify an options file if you want to use a different compiler (and not use the -setup option), or you want to compile MAT or engine standalone programs.
A selected compiler configuration specifies the compiler and build options MATLAB uses every time you invoke the mex build script. The compiler in this configuration is the selected compiler. It is the program that compiles source code into object code. A configuration is the set of programs and instructions that builds source code into shared libraries and standalone executable files.
To select a configuration, use the mex -setup command. You can set or change the configuration anytime, from either the MATLAB or the system command prompt. After you choose a configuration, it becomes the default and you no longer have to select one to compile MEX-files.
You can view information about the selected compiler configuration using the mex.getCompilerConfigurations function.
You can change the compiler configuration for a single call to the mex script using the -f switch, which specifies an options file. Subsequent calls to mex continue to use the selected compiler configuration.
For more information about these topics, see:
You can set or change your compiler configuration anytime from either the MATLAB command prompt or the UNIX shell, using the command:
mex -setup
MATLAB shows you the available compiler configurations, called options files, in the following message:
Options files control which compiler to use, the compiler and link command options, and the runtime libraries to link against. Using the 'mex -setup' command selects an options file that is placed in ~/.matlab/R2008a and used by default for 'mex'. An options file in the current working directory or specified on the command line overrides the default options file in ~/.matlab/R2008a. To override the default options file, use the 'mex -f' command (see 'mex -help' for more information).
MATLAB generates a list similar to the following:
The options files available for mex are:
1: /mathworks/AH/devel/bat/Akernel/perfect/matlab/bin/f90opts.sh :
Template Options file for building Fortran 90 MEX-files via the
system ANSI compiler
2: /mathworks/AH/devel/bat/Akernel/perfect/matlab/bin/gccopts.sh :
Template Options file for building gcc MEX-files
3: /mathworks/AH/devel/bat/Akernel/perfect/matlab/bin/mexopts.sh :
Template Options file for building MEX-files via the system ANSI
compiler
0: Exit with no changes
To choose the compiler you want to use, respond to the MATLAB prompt:
Enter the number of the compiler (0-3):
Type the number corresponding to your selection. (If you do not want to change your configuration, type 0. MATLAB returns to the command prompt.) MATLAB displays information similar to the following:
matlabroot/bin/gccopts.sh is being copied to /home/auser/.matlab/R2008a/mexopts.sh
On UNIX systems, there are three configurations, one for each compiler language (C, C++ and Fortran). Use the mex.getCompilerConfigurations function to view details about the compiler configurations.
To get information about the your compiler configuration, type:
cc = mex.getCompilerConfigurations
MATLAB creates a mex.CompilerConfiguration object cc and displays its properties:
cc =
1x3 mex.CompilerConfiguration
package: mex
properties:
Name
Manufacturer
Language
Version
Location
Details
list of methods
On the UNIX platform, cc is an array of three CompilerConfiguration objects – one for each language (C, C++, and Fortran). To see the compiler names, type:
disp('Compiler Name')
for i = 1:3; disp(cc(i).Name); end;
MATLAB displays:
Compiler Name GNU C GNU C++ g95
Note On UNIX systems, mex.CompilerConfiguration.Location is an empty string |
MATLAB includes template options files you can use with particular compilers. The options files are located in the matlabroot/bin directory.
The UNIX options file is named *opts.sh, where * is either mex or a specific compiler name.
For information on how to modify options files for particular systems, see Custom Building MEX-Files.
Use the -f option to specify an options file. To use this option, at the MATLAB prompt, type:
mex filename -f optionsfile
where optionsfile is the full path to the options file.
You might need to specify an options file in the following situations:
You want to use a different compiler (and not use the -setup option), or you want to compile MAT or engine standalone programs.
You do not want to use the system C compiler.
MATLAB provides an example MEX-file, timestwo, for you to use to configure your system. This function takes a scalar input and doubles it.
The C source file is timestwo.c, and the Fortran source file is timestwo.F. These files are in the matlabroot\extern\examples\refbook directory, where matlabroot is the MATLAB root directory, the value returned by the matlabroot command.
To work with these files, copy them to a local directory. For example:
cd('c:\work')
copyfile([matlabroot '\extern\examples\refbook\timestwo.c'])
copyfile([matlabroot '\extern\examples\refbook\timestwo.F'])
To select your compiler, follow the instructions in either Selecting a Compiler on UNIX Platforms or Selecting a Compiler on Windows Platforms.
Use the mex function to build the binary MEX-file. If you are using a C compiler, type:
mex timestwo.c
If you are using a Fortran compiler, type:
mex timestwo.F
This command creates the file timestwo.mexext, where mexext is the value returned by the mexext function. You call timestwo as if it were an M-function. For example, at the MATLAB command prompt, type:
timestwo(4)
MATLAB displays:
ans =
8
Note In a future version of MATLAB, the default mex function will change to use the large-array-handling API. This means the -largeArrayDims option will be the default. For information about mex options, see MEX Script Switches. For information about the large-array-handling API, see Handling Large mxArrays. |
| MATLAB Data | Custom Building MEX-Files | |
| © 1984-2008- The MathWorks, Inc. - Site Help - Patents - Trademarks - Privacy Policy - Preventing Piracy - RSS |