If you use makefiles to build your GCC* application, you need to change the value for the GCC compiler variable to use the Intel® C++ Compiler Classic. You may also want to review the options specified by CFLAGS. For example:
Sample GCC makefile |
---|
|
Sample makefile modified for the Intel® C++ Compiler Classic |
---|
|
Where [invocation] is icc.
If your GCC code includes features that are not supported with the Intel® C++ Compiler Classic (compiler options, language extensions, macros, pragmas, and so on), you can compile those sources separately with GCC if necessary.
In the above makefile, area_functions.c is an example of a source file that includes features unique to GCC. Because the Intel® C++ Compiler Classic uses the O2 option by default and GCC uses option O0 as the default, we instruct GCC to compile at option O2. We also include the -fno-asm switch from the original makefile because this switch is not supported with the Intel® C++ Compiler Classic.
Sample makefile modified for using the Intel® C++ Compiler Classic and GCC together |
---|
|
Where [invocation] is icc.
Output of make using a modified makefile |
---|
|
Where [invocation] is icc.
Use IPO in Makefiles
By default, IPO generates "dummy" object files containing Interprocedural information used by the compiler. To link or create static libraries with these object files requires special Intel®-provided tools. To use them in your makefile, simply replace references to "ld" with "xild" and references to "ar" with "xiar", or use icc to link as shown below.
Sample makefile modified for the Intel® C++ Compiler Classic with IPO |
---|
|
Where [invocation] is icc.