diff options
Diffstat (limited to 'tools/build/Documentation/Build.txt')
| -rw-r--r-- | tools/build/Documentation/Build.txt | 52 |
1 files changed, 39 insertions, 13 deletions
diff --git a/tools/build/Documentation/Build.txt b/tools/build/Documentation/Build.txt index aa5e092c4352..a47bffbae159 100644 --- a/tools/build/Documentation/Build.txt +++ b/tools/build/Documentation/Build.txt @@ -11,8 +11,9 @@ Unlike the kernel we don't have a single build object 'obj-y' list that where we setup source objects, but we support more. This allows one 'Build' file to carry a sources list for multiple build objects. -a) Build framework makefiles ----------------------------- + +Build framework makefiles +------------------------- The build framework consists of 2 Makefiles: @@ -23,7 +24,7 @@ While the 'Build.include' file contains just some generic definitions, the 'Makefile.build' file is the makefile used from the outside. It's interface/usage is following: - $ make -f tools/build/Makefile srctree=$(KSRC) dir=$(DIR) obj=$(OBJECT) + $ make -f tools/build/Makefile.build srctree=$(KSRC) dir=$(DIR) obj=$(OBJECT) where: @@ -38,8 +39,9 @@ called $(OBJECT)-in.o: which includes all compiled sources described in 'Build' makefiles. -a) Build makefiles ------------------- + +Build makefiles +--------------- The user supplies 'Build' makefiles that contains a objects list, and connects the build to nested directories. @@ -95,8 +97,31 @@ It's only a matter of 2 single commands to create the final binaries: You can check the 'ex' example in 'tools/build/tests/ex' for more details. -b) Rules --------- + +Makefile.include +---------------- + +The tools/build/Makefile.include makefile could be included +via user makefiles to get usefull definitions. + +It defines following interface: + + - build macro definition: + build := -f $(srctree)/tools/build/Makefile.build dir=. obj + + to make it easier to invoke build like: + make $(build)=ex + + +Fixdep +------ +It is necessary to build the fixdep helper before invoking the build. +The Makefile.include file adds the fixdep target, that could be +invoked by the user. + + +Rules +----- The build framework provides standard compilation rules to handle .S and .c compilation. @@ -104,8 +129,9 @@ compilation. It's possible to include special rule if needed (like we do for flex or bison code generation). -c) CFLAGS ---------- + +CFLAGS +------ It's possible to alter the standard object C flags in the following way: @@ -115,8 +141,8 @@ It's possible to alter the standard object C flags in the following way: This C flags changes has the scope of the Build makefile they are defined in. -d) Dependencies ---------------- +Dependencies +------------ For each built object file 'a.o' the '.a.cmd' is created and holds: @@ -130,8 +156,8 @@ All existing '.cmd' files are included in the Build process to follow properly the dependencies and trigger a rebuild when necessary. -e) Single rules ---------------- +Single rules +------------ It's possible to build single object file by choice, like: |