LTO: Prevent -flto from creating crashing kernels.
[dragonfly.git] / sys / conf / kern.pre.mk
1 #
2 # This Makefile covers the top part of the MI kernel build instructions
3 #
4
5 # Can be overridden by makeoptions or /etc/make.conf
6 KERNEL?=        kernel
7
8 # build this target if none is specified on the command line
9 .MAIN:  all
10
11 # Set the platform and machine architectures
12 #
13 P=      ${MACHINE_PLATFORM}
14 M=      ${MACHINE_ARCH}
15
16 SIZE?=          size
17 OBJCOPY?=       objcopy
18
19 COPTFLAGS?=-O -pipe
20 #COPTFLAGS?=-O -pipe -flto -fno-fat-lto-objects
21 #COPTFLAGS?=-O -fthread-jumps -fcse-follow-jumps -fcrossjumping -frerun-cse-after-loop -fno-guess-branch-probability --param min-crossjump-insns=1 -pipe
22 #COPTFLAGS?=-O -fcrossjumping -pipe
23 #COPTFLAGS?=-Os -fno-strict-aliasing -pipe
24 #COPTFLAGS?=-O2 -fno-strict-aliasing -pipe
25 .if !defined(NO_CPU_COPTFLAGS)
26 COPTFLAGS+= ${_CPUCFLAGS}
27 .endif
28 # don't use -I- so we can use proper source-relative locality for local 
29 # includes.
30 #
31 # -I.  - this is to access the opt_*.h and use_*.h header files generated
32 #        in the kernel build directory.
33 #
34 # -Iinclude
35 #       - this is used to access forwarding header files for
36 #         <machine/*.h> that exist in the cpu architecture but do not
37 #         exist in the platform (machine/) architecture.  This allows
38 #         the platform to trivially override the cpu header files.
39 #
40 INCLUDES= -nostdinc -I. -Iinclude -I$S
41 # This hack is to allow kernel compiles to succeed on machines w/out srcdist
42 .if exists($S/../include)
43 INCLUDES+= -I$S/../include
44 .else
45 INCLUDES+= -I/usr/include
46 .endif
47
48 # This hack lets us use the Intel ACPICA code without spamming a new
49 # include path into 100+ source files.
50 .include "$S/conf/acpi.mk"
51 INCLUDES+= -I${.OBJDIR} -I"$S/${OSACPI_MI_DIR}" -I"$S/${ACPICA_DIR}/include"
52
53 # ... and the same for Atheros HAL
54 INCLUDES+= -I$S/dev/netif/ath/ath_hal -I$S/contrib/dev/ath/ath_hal
55
56 # Same thing for drm includes
57 INCLUDES+= -I$S/dev/drm/include
58
59 COPTS=  ${INCLUDES} ${IDENT} -D_KERNEL -DHAVE_KERNEL_OPTION_HEADERS -include opt_global.h
60 CFLAGS= ${COPTFLAGS} ${CWARNFLAGS} ${DEBUG} ${COPTS}
61
62 # XXX LOCORE means "don't declare C stuff" not "for locore.s".
63 ASM_CFLAGS= -x assembler-with-cpp -DLOCORE ${CFLAGS:N-flto}
64
65 DEFINED_PROF=   ${PROF}
66 .if defined(PROF)
67 CFLAGS+=        -falign-functions=16
68 .if ${PROFLEVEL} >= 2
69 IDENT+= -DGPROF4 -DGUPROF
70 PROF+=  -mprofiler-epilogue
71 .endif
72 .endif
73
74 # Put configuration-specific C flags last (except for ${PROF}) so that they
75 # can override the others.
76 CFLAGS+=        ${CONF_CFLAGS}
77
78 NORMAL_C= ${CC} -c ${CFLAGS} ${PROF} ${.IMPSRC}
79 NORMAL_C_C= ${CC} -c ${CFLAGS} ${PROF} ${.IMPSRC}
80 NORMAL_S= ${CC} -c ${ASM_CFLAGS} ${.IMPSRC}
81 PROFILE_C= ${CC} -c ${CFLAGS} ${.IMPSRC}
82
83 NORMAL_M= awk -f $S/tools/makeobjops.awk -- -c $<; \
84         ${CC} -c ${CFLAGS} ${PROF} ${.PREFIX}.c
85
86 NORMAL_FW= uudecode -o ${.TARGET} ${.ALLSRC}
87 NORMAL_FWO= ${LD} -b binary -d -warn-common -r -o ${.TARGET} ${.ALLSRC:M*.fw}
88
89 .if !defined(NO_WERROR) && (${CCVER} == "gcc47" || ${CCVER} == "gcc50")
90 WERROR=-Werror
91 .endif
92
93 GEN_CFILES= $S/platform/$P/$M/genassym.c
94 SYSTEM_CFILES= ioconf.c config.c
95 SYSTEM_SFILES= $S/platform/$P/$M/locore.s
96 SYSTEM_DEP= Makefile ${SYSTEM_OBJS}
97 SYSTEM_OBJS= locore.o ${OBJS} ioconf.o config.o hack.So
98 SYSTEM_LD= @${CC} -nostdlib -ffreestanding -Wl,--hash-style=sysv \
99         -Wl,-Bdynamic -Wl,-T,$S/platform/$P/conf/ldscript.$M \
100         -Wl,--export-dynamic -Wl,--dynamic-linker,/red/herring \
101         -o ${.TARGET} -Wl,-X ${SYSTEM_OBJS} vers.o
102
103 # In case of LTO provide all standard CFLAGS!
104 .if ${CFLAGS:M-flto}
105 SYSTEM_LD+= ${CFLAGS}
106 # XXX this one eats a lot of ram, but needed to correctly link the kernel.
107 # Default "balanced" might create kernel that "Fatal trap 12" on boot!!!
108 . if !${CFLAGS:M-flto-partition=*}
109 SYSTEM_LD+= -flto-partition=one -flto-report-wpa
110 . endif
111 .endif
112
113 # The max-page-size for gnu ld is 0x200000 on x86_64
114 # For the gold linker, it is only 0x1000 on both x86_64 and i386
115 # The penalty for changing the gold default for x86_64 is larger binaries
116 # and shared libraries, and forcing them to use more address space than
117 # required.  The only application that needs such a large page size is the
118 # kernel itself, so leave the gold default alone and treat the kernel
119 # page size as an exception.
120 #
121 .if ${P} == "pc64"
122 SYSTEM_LD+= -Wl,-z,max-page-size=0x200000
123 .endif
124
125 SYSTEM_LD_TAIL= @${OBJCOPY} --strip-symbol gcc2_compiled. ${.TARGET} ; \
126         ${SIZE} ${.TARGET} ; chmod 755 ${.TARGET}
127 SYSTEM_DEP+= $S/platform/$P/conf/ldscript.$M
128
129 # Normalize output files to make it absolutely crystal clear to
130 # anyone examining the build directory.
131 #
132 .if defined(DEBUG)
133 FULLKERNEL=     ${KERNEL}.debug
134 .if defined(INSTALLSTRIPPED)
135 SELECTEDKERNEL= ${KERNEL}.stripped
136 .else
137 SELECTEDKERNEL= ${KERNEL}.debug
138 .endif
139 .else
140 FULLKERNEL=     ${KERNEL}.nodebug
141 SELECTEDKERNEL= ${KERNEL}.stripped
142 .endif
143
144
145 MKMODULESENV=   MAKEOBJDIRPREFIX=${.OBJDIR} BUILDING_WITH_KERNEL=${.OBJDIR}
146 .if defined(MODULES_OVERRIDE)
147 MKMODULESENV+=  MODULES_OVERRIDE="${MODULES_OVERRIDE}"
148 .endif
149 .if defined(DEBUG)
150 MKMODULESENV+=  DEBUG="${DEBUG}" DEBUG_FLAGS="${DEBUG}"
151 .endif
152 .if defined(INSTALLSTRIPPED) || defined(INSTALLSTRIPPEDMODULES)
153 MKMODULESENV+=  INSTALLSTRIPPEDMODULES=1
154 .endif
155 MKMODULESENV+=  MACHINE_ARCH=${MACHINE_ARCH} MACHINE=${MACHINE} MACHINE_PLATFORM=${MACHINE_PLATFORM}
156