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Based on kernel version 3.15.4. Page generated on 2014-07-07 09:03 EST.

1	Output files
2	
3	modules.order
4	--------------------------------------------------
5	This file records the order in which modules appear in Makefiles. This
6	is used by modprobe to deterministically resolve aliases that match
7	multiple modules.
8	
9	modules.builtin
10	--------------------------------------------------
11	This file lists all modules that are built into the kernel. This is used
12	by modprobe to not fail when trying to load something builtin.
13	
14	
15	Environment variables
16	
17	KCPPFLAGS
18	--------------------------------------------------
19	Additional options to pass when preprocessing. The preprocessing options
20	will be used in all cases where kbuild does preprocessing including
21	building C files and assembler files.
22	
23	KAFLAGS
24	--------------------------------------------------
25	Additional options to the assembler (for built-in and modules).
26	
27	AFLAGS_MODULE
28	--------------------------------------------------
29	Additional module specific options to use for $(AS).
30	
31	AFLAGS_KERNEL
32	--------------------------------------------------
33	Additional options for $(AS) when used for assembler
34	code for code that is compiled as built-in.
35	
36	KCFLAGS
37	--------------------------------------------------
38	Additional options to the C compiler (for built-in and modules).
39	
40	CFLAGS_KERNEL
41	--------------------------------------------------
42	Additional options for $(CC) when used to compile
43	code that is compiled as built-in.
44	
45	CFLAGS_MODULE
46	--------------------------------------------------
47	Additional module specific options to use for $(CC).
48	
49	LDFLAGS_MODULE
50	--------------------------------------------------
51	Additional options used for $(LD) when linking modules.
52	
53	LDFLAGS_vmlinux
54	--------------------------------------------------
55	Additional options passed to final link of vmlinux.
56	
57	KBUILD_VERBOSE
58	--------------------------------------------------
59	Set the kbuild verbosity. Can be assigned same values as "V=...".
60	See make help for the full list.
61	Setting "V=..." takes precedence over KBUILD_VERBOSE.
62	
63	KBUILD_EXTMOD
64	--------------------------------------------------
65	Set the directory to look for the kernel source when building external
66	modules.
67	The directory can be specified in several ways:
68	1) Use "M=..." on the command line
69	2) Environment variable KBUILD_EXTMOD
70	3) Environment variable SUBDIRS
71	The possibilities are listed in the order they take precedence.
72	Using "M=..." will always override the others.
73	
74	KBUILD_OUTPUT
75	--------------------------------------------------
76	Specify the output directory when building the kernel.
77	The output directory can also be specified using "O=...".
78	Setting "O=..." takes precedence over KBUILD_OUTPUT.
79	
80	KBUILD_DEBARCH
81	--------------------------------------------------
82	For the deb-pkg target, allows overriding the normal heuristics deployed by
83	deb-pkg. Normally deb-pkg attempts to guess the right architecture based on
84	the UTS_MACHINE variable, and on some architectures also the kernel config.
85	The value of KBUILD_DEBARCH is assumed (not checked) to be a valid Debian
86	architecture.
87	
88	ARCH
89	--------------------------------------------------
90	Set ARCH to the architecture to be built.
91	In most cases the name of the architecture is the same as the
92	directory name found in the arch/ directory.
93	But some architectures such as x86 and sparc have aliases.
94	x86: i386 for 32 bit, x86_64 for 64 bit
95	sparc: sparc for 32 bit, sparc64 for 64 bit
96	
97	CROSS_COMPILE
98	--------------------------------------------------
99	Specify an optional fixed part of the binutils filename.
100	CROSS_COMPILE can be a part of the filename or the full path.
101	
102	CROSS_COMPILE is also used for ccache in some setups.
103	
104	CF
105	--------------------------------------------------
106	Additional options for sparse.
107	CF is often used on the command-line like this:
108	
109	    make CF=-Wbitwise C=2
110	
111	INSTALL_PATH
112	--------------------------------------------------
113	INSTALL_PATH specifies where to place the updated kernel and system map
114	images. Default is /boot, but you can set it to other values.
115	
116	INSTALLKERNEL
117	--------------------------------------------------
118	Install script called when using "make install".
119	The default name is "installkernel".
120	
121	The script will be called with the following arguments:
122	    $1 - kernel version
123	    $2 - kernel image file
124	    $3 - kernel map file
125	    $4 - default install path (use root directory if blank)
126	
127	The implementation of "make install" is architecture specific
128	and it may differ from the above.
129	
130	INSTALLKERNEL is provided to enable the possibility to
131	specify a custom installer when cross compiling a kernel.
132	
133	MODLIB
134	--------------------------------------------------
135	Specify where to install modules.
136	The default value is:
137	
138	     $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
139	
140	The value can be overridden in which case the default value is ignored.
141	
142	INSTALL_MOD_PATH
143	--------------------------------------------------
144	INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
145	relocations required by build roots.  This is not defined in the
146	makefile but the argument can be passed to make if needed.
147	
148	INSTALL_MOD_STRIP
149	--------------------------------------------------
150	INSTALL_MOD_STRIP, if defined, will cause modules to be
151	stripped after they are installed.  If INSTALL_MOD_STRIP is '1', then
152	the default option --strip-debug will be used.  Otherwise,
153	INSTALL_MOD_STRIP value will be used as the options to the strip command.
154	
155	INSTALL_FW_PATH
156	--------------------------------------------------
157	INSTALL_FW_PATH specifies where to install the firmware blobs.
158	The default value is:
159	
160	    $(INSTALL_MOD_PATH)/lib/firmware
161	
162	The value can be overridden in which case the default value is ignored.
163	
164	INSTALL_HDR_PATH
165	--------------------------------------------------
166	INSTALL_HDR_PATH specifies where to install user space headers when
167	executing "make headers_*".
168	The default value is:
169	
170	    $(objtree)/usr
171	
172	$(objtree) is the directory where output files are saved.
173	The output directory is often set using "O=..." on the commandline.
174	
175	The value can be overridden in which case the default value is ignored.
176	
177	KBUILD_MODPOST_WARN
178	--------------------------------------------------
179	KBUILD_MODPOST_WARN can be set to avoid errors in case of undefined
180	symbols in the final module linking stage. It changes such errors
181	into warnings.
182	
183	KBUILD_MODPOST_NOFINAL
184	--------------------------------------------------
185	KBUILD_MODPOST_NOFINAL can be set to skip the final link of modules.
186	This is solely useful to speed up test compiles.
187	
188	KBUILD_EXTRA_SYMBOLS
189	--------------------------------------------------
190	For modules that use symbols from other modules.
191	See more details in modules.txt.
192	
193	ALLSOURCE_ARCHS
194	--------------------------------------------------
195	For tags/TAGS/cscope targets, you can specify more than one arch
196	to be included in the databases, separated by blank space. E.g.:
197	
198	    $ make ALLSOURCE_ARCHS="x86 mips arm" tags
199	
200	To get all available archs you can also specify all. E.g.:
201	
202	    $ make ALLSOURCE_ARCHS=all tags
203	
204	KBUILD_ENABLE_EXTRA_GCC_CHECKS
205	--------------------------------------------------
206	If enabled over the make command line with "W=1", it turns on additional
207	gcc -W... options for more extensive build-time checking.
208	
209	KBUILD_BUILD_TIMESTAMP
210	--------------------------------------------------
211	Setting this to a date string overrides the timestamp used in the
212	UTS_VERSION definition (uname -v in the running kernel). The value has to
213	be a string that can be passed to date -d. The default value
214	is the output of the date command at one point during build.
215	
216	KBUILD_BUILD_USER, KBUILD_BUILD_HOST
217	--------------------------------------------------
218	These two variables allow to override the user@host string displayed during
219	boot and in /proc/version. The default value is the output of the commands
220	whoami and host, respectively.
221	
222	KBUILD_LDS
223	--------------------------------------------------
224	The linker script with full path. Assigned by the top-level Makefile.
225	
226	KBUILD_VMLINUX_INIT
227	--------------------------------------------------
228	All object files for the init (first) part of vmlinux.
229	Files specified with KBUILD_VMLINUX_INIT are linked first.
230	
231	KBUILD_VMLINUX_MAIN
232	--------------------------------------------------
233	All object files for the main part of vmlinux.
234	KBUILD_VMLINUX_INIT and KBUILD_VMLINUX_MAIN together specify
235	all the object files used to link vmlinux.
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