User`s guide

Cray XMT™ Programming Environment User’s Guide
When you use the -pl and -c options to compile a source file, the compiler
performs the following tasks during the compilation phase:
• Checks the source for syntax errors
• Creates an internal representation of each function in the program library
• Produces a skinny .o file
During the linking phase, the compiler performs the following tasks to create an
executable:
• Performs optimizations using information about the complete program
• Builds objects for each module
• Links the modules together to produce an executable
• Stores objects in the program library to support incremental recompilation
As in traditional UNIX compilation, the -o flag specifies the executable name
explicitly. To do this, use the following command:
c++ -pl test.pl -o test svd.o ddot.o
The previous command links the svd and ddot modules that reside in test.pl
and creates the executable in a file called test.
You can also specify multistep command sequences that use a mix of source and
object files when using whole-program mode. To do this, use the following sequence
of commands:
c++ -pl a.out.pl -c ddot.cc
c++ -pl a.out.pl arnoldi.cc ddot.o
The first command partially compiles ddot.cc. The second command partially
compiles arnoldi.cc; completes compilation and optimization of the modules
ddot and arnoldi; links arnoldi, ddot, and any required libraries; and places
the resulting executable in a.out. The compiler optimizes each function using
information about the ddot and arnoldi modules.
7.3.2 Separate-module Mode
-pl flag to compilation and link lines. Separate-module mode also prevents the
propagation of changes made in one module to other modules. This greatly reduces
the level of optimization that occurs when using separate-module mode compared to
that of whole-program mode.
To compile a single source file into its corresponding object file, use the following
command.
c++ -c ddot.cc
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