HP Integrity NonStop J-Series - Manual (Page 52)

This table lists the three automatically-generated makefiles that are written to the top-level build
directory:
Purpose Makefile
The primary makefile for a build configuration. It contains the build rules for "all", "clean",
and "deploy". makefile
Contains definitions of USER_OBJS and LIBS, two build macros that are set to
out-of-project object files and libraries, respectively, that are passed to the linker for the
final link step. objects.mk
Defines a list of source macros, such as C_SRCS, and all of the subdirectories that
contribute source code to the build. sources.mk
NSDEE also creates a makefile for each source directory containing sources to be built. The source
directory names and hierarchy are mirrored under a Debug or Release folder (depending on the
build configuration). For each such mirrored directory, NSDEE creates a subdir.mk file which
contains the rules for building the sources in the containing directory. Mirrored directories also
contain the build output of source built from the original source directory.
Figure 8 (page 52) shows
the layout of a simple project with one source directory named src and one top-level build directory
named Debug.
Figure 8 Layout of simple project
Handling dependencies in managed builds
To ensure C and C++ objects are rebuilt when dependent header files are changed, NSDEE adds
build-rules commands to generate dependency files.
How managed makefiles create dependency files
For C and C++, NSDEE-generated makefiles generate header file dependencies for objects by
re-running the compiler invocation with the addition of the -WM option (so the compiler lists
dependencies). The second compiler invocation is part of the same build rule that builds the object
file. This ensures that every time a particular object file is built, the header file dependencies for
that file are regenerated.
Example 3 “Sample build rule for Door.o in subdir.mk” shows an example of a build rule for an
object file named Door.o in a subdir.mk file for a project named CarParts.
52 Concepts