tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
ARC: Adjustments for gcc 4.8
* DWARF unwinder related
+ Force DWARF2 compliant .debug_frame (gcc 4.8 defaults to DWARF4
which kernel unwinder can't grok).
+ Discard the additional .eh_frame generated
+ Discard the dwarf4 debug info generated by -gdwarf-2 for normal
no debug case
* 4.8 already uses arc600 multilibs for -mno-mpy
* switch to using uclibc compiler (to get -mmedium-calls and -mno-sdata)
and also since buildroot can only use 1 toolchain
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
+35
-19
+16
-8
arch/arc/Makefile
+16
-8
arch/arc/Makefile
···
9
9
UTS_MACHINE := arc
10
10
11
11
ifeq ($(CROSS_COMPILE),)
12
-
CROSS_COMPILE := arc-elf32-
12
+
CROSS_COMPILE := arc-linux-uclibc-
13
13
endif
14
14
15
15
KBUILD_DEFCONFIG := fpga_defconfig
···
25
25
LINUXINCLUDE += -include ${src}/arch/arc/include/asm/current.h
26
26
endif
27
27
28
-
atleast_gcc44 := $(call cc-ifversion, -gt, 0402, y)
28
+
upto_gcc42 := $(call cc-ifversion, -le, 0402, y)
29
+
upto_gcc44 := $(call cc-ifversion, -le, 0404, y)
30
+
atleast_gcc44 := $(call cc-ifversion, -ge, 0404, y)
31
+
atleast_gcc48 := $(call cc-ifversion, -ge, 0408, y)
32
+
29
33
cflags-$(atleast_gcc44) += -fsection-anchors
30
34
31
35
cflags-$(CONFIG_ARC_HAS_LLSC) += -mlock
32
36
cflags-$(CONFIG_ARC_HAS_SWAPE) += -mswape
33
37
cflags-$(CONFIG_ARC_HAS_RTSC) += -mrtsc
34
38
cflags-$(CONFIG_ARC_DW2_UNWIND) += -fasynchronous-unwind-tables
39
+
40
+
# By default gcc 4.8 generates dwarf4 which kernel unwinder can't grok
41
+
ifeq ($(atleast_gcc48),y)
42
+
cflags-$(CONFIG_ARC_DW2_UNWIND) += -gdwarf-2
43
+
endif
35
44
36
45
ifndef CONFIG_CC_OPTIMIZE_FOR_SIZE
37
46
# Generic build system uses -O2, we want -O3
···
55
46
cflags-$(CONFIG_CPU_BIG_ENDIAN) += -mbig-endian
56
47
ldflags-$(CONFIG_CPU_BIG_ENDIAN) += -EB
57
48
58
-
# STAR 9000518362:
49
+
# STAR 9000518362: (fixed with binutils shipping with gcc 4.8)
59
50
# arc-linux-uclibc-ld (buildroot) or arceb-elf32-ld (EZChip) don't accept
60
-
# --build-id w/o "-marclinux".
61
-
# Default arc-elf32-ld is OK
62
-
ldflags-y += -marclinux
51
+
# --build-id w/o "-marclinux". Default arc-elf32-ld is OK
52
+
ldflags-$(upto_gcc44) += -marclinux
63
53
64
54
ARC_LIBGCC := -mA7
65
55
cflags-$(CONFIG_ARC_HAS_HW_MPY) += -multcost=16
···
72
64
# With gcc 4.4.7, -mno-mpy is enough to make any other related adjustments,
73
65
# e.g. increased cost of MPY. With gcc 4.2.1 this had to be explicitly hinted
74
66
75
-
ARC_LIBGCC := -marc600
76
-
ifneq ($(atleast_gcc44),y)
67
+
ifeq ($(upto_gcc42),y)
68
+
ARC_LIBGCC := -marc600
77
69
cflags-y += -multcost=30
78
70
endif
79
71
endif
+1
-1
arch/arc/configs/fpga_defconfig
+1
-1
arch/arc/configs/fpga_defconfig
+1
-1
arch/arc/configs/nsimosci_defconfig
+1
-1
arch/arc/configs/nsimosci_defconfig
+1
-1
arch/arc/configs/tb10x_defconfig
+1
-1
arch/arc/configs/tb10x_defconfig
+16
-8
arch/arc/kernel/vmlinux.lds.S
+16
-8
arch/arc/kernel/vmlinux.lds.S
···
125
125
*(.debug_frame)
126
126
__end_unwind = .;
127
127
}
128
+
/*
129
+
* gcc 4.8 generates this for -fasynchonous-unwind-tables,
130
+
* while we still use the .debug_frame based unwinder
131
+
*/
132
+
/DISCARD/ : { *(.eh_frame) }
128
133
#else
129
134
/DISCARD/ : { *(.debug_frame) }
130
135
#endif
···
147
142
*(.arcextmap.*)
148
143
}
149
144
145
+
#ifndef CONFIG_DEBUG_INFO
150
146
/* open-coded because we need .debug_frame seperately for unwinding */
151
-
.debug_aranges 0 : { *(.debug_aranges) }
152
-
.debug_pubnames 0 : { *(.debug_pubnames) }
153
-
.debug_info 0 : { *(.debug_info) }
154
-
.debug_abbrev 0 : { *(.debug_abbrev) }
155
-
.debug_line 0 : { *(.debug_line) }
156
-
.debug_str 0 : { *(.debug_str) }
157
-
.debug_loc 0 : { *(.debug_loc) }
158
-
.debug_macinfo 0 : { *(.debug_macinfo) }
147
+
/DISCARD/ : { *(.debug_aranges) }
148
+
/DISCARD/ : { *(.debug_pubnames) }
149
+
/DISCARD/ : { *(.debug_info) }
150
+
/DISCARD/ : { *(.debug_abbrev) }
151
+
/DISCARD/ : { *(.debug_line) }
152
+
/DISCARD/ : { *(.debug_str) }
153
+
/DISCARD/ : { *(.debug_loc) }
154
+
/DISCARD/ : { *(.debug_macinfo) }
155
+
/DISCARD/ : { *(.debug_ranges) }
156
+
#endif
159
157
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158
#ifdef CONFIG_ARC_HAS_DCCM
161
159
. = CONFIG_ARC_DCCM_BASE;