Hi,
I'd like to understand how gcc options be used in Make variables.
In Option Summary of the man page of gcc, I see many sections about
options, like the following. What should be in CFLAGS, CXXFLAGS,
CPPFLAGS and LDFLAGS, respectively?
For example, should -g be used in CPPFLAGS or both CFLAGS and
CXXFLAGS? Should it be used with LDFLAGS? What about -O2? Thanks.
Overall Options
C Language Options
C++ Language Options
Objective-C and Objective-C++ Language Options
Language Independent Options
Warning Options
C and Objective-C-only Warning Options
Debugging Options
Optimization Options
Preprocessor Options
Linker Options
Directory Options
Machine Dependent Options
AArch64 Options -mabi=name -mbig-endian -mlittle-endian
Adapteva Epiphany Options -mhalf-reg-file -mprefer-short-insn-regs
ARC Options -mbarrel-shifter -mcpu=cpu -mA6 -mARC600 -mA7 -mARC700
ARM Options -mapcs-frame -mno-apcs-frame -mabi=name
AVR Options -mmcu=mcu -maccumulate-args -mbranch-cost=cost
Blackfin Options -mcpu=cpu[-sirevision] -msim
C6X Options -mbig-endian -mlittle-endian -march=cpu -msim
CRIS Options -mcpu=cpu -march=cpu -mtune=cpu -mmax-stack-frame=n
CR16 Options -mmac -mcr16cplus -mcr16c -msim -mint32 -mbit-ops
Darwin Options -all_load -allowable_client -arch
DEC Alpha Options -mno-fp-regs -msoft-float -mieee
FR30 Options -msmall-model -mno-lsim
FRV Options -mgpr-32 -mgpr-64 -mfpr-32 -mfpr-64 -mhard-float
GNU/Linux Options -mglibc -muclibc -mbionic -mandroid
H8/300 Options -mrelax -mh -ms -mn -mexr -mno-exr -mint32
HPPA Options -march=architecture-type -mdisable-fpregs
IA-64 Options -mbig-endian -mlittle-endian -mgnu-as -mgnu-ld
LM32 Options -mbarrel-shift-enabled -mdivide-enabled
M32R/D Options -m32r2 -m32rx -m32r -mdebug -malign-loops
M32C Options -mcpu=cpu -msim -memregs=number
M680x0 Options -march=arch -mcpu=cpu -mtune=tune -m68000 -m68020
MCore Options -mhardlit -mno-hardlit -mdiv -mno-div
MeP Options -mabsdiff -mall-opts -maverage -mbased=n -mbitops -mc=n
MicroBlaze Options -msoft-float -mhard-float -msmall-divides
MIPS Options -EL -EB -march=arch -mtune=arch -mips1 -mips2
MMIX Options -mlibfuncs -mno-libfuncs -mepsilon -mno-epsilon
MN10300 Options -mmult-bug -mno-mult-bug -mno-am33 -mam33 -mam33-2
Moxie Options -meb -mel -mmul.x -mno-crt0
MSP430 Options -msim -masm-hex -mmcu= -mcpu= -mlarge -msmall
NDS32 Options -mbig-endian -mlittle-endian -mreduced-regs
Nios II Options -G num -mgpopt=option -mgpopt -mno-gpopt -mel -meb
Nvidia PTX Options -m32 -m64 -mmainkernel
PDP-11 Options -mfpu -msoft-float -mac0 -mno-ac0 -m40 -m45
picoChip Options -mae=ae_type -mvliw-lookahead=N
PowerPC Options See RS/6000 and PowerPC Options.
RL78 Options -msim -mmul=none -mmul=g13 -mmul=rl78 -m64bit-doubles
RS/6000 and PowerPC Options -mcpu=cpu-type -mtune=cpu-type
RX Options -m64bit-doubles -m32bit-doubles -fpu -nofpu -mcpu=
S/390 and zSeries Options -mtune=cpu-type -march=cpu-type
Score Options -meb -mel -mnhwloop -muls -mmac -mscore5 -mscore5u
SH Options -m1 -m2 -m2e -m2a-nofpu -m2a-single-only -m2a-single
Solaris 2 Options -mclear-hwcap -mno-clear-hwcap -mimpure-text
SPARC Options -mcpu=cpu-type -mtune=cpu-type -mcmodel=code-model
SPU Options -mwarn-reloc -merror-reloc -msafe-dma -munsafe-dma
System V Options -Qy -Qn -YP,paths -Ym,dir
TILE-Gx Options -mcpu=CPU -m32 -m64 -mbig-endian -mlittle-endian
TILEPro Options -mcpu=cpu -m32
V850 Options -mlong-calls -mno-long-calls -mep -mno-ep
VAX Options -mg -mgnu -munix
Visium Options -mdebug -msim -mfpu -mno-fpu -mhard-float
VMS Options -mvms-return-codes -mdebug-main=prefix -mmalloc64
VxWorks Options -mrtp -non-static -Bstatic -Bdynamic -Xbind-lazy
x86 Options -mtune=cpu-type -march=cpu-type -mtune-ctrl=feature-
x86 Windows Options -mconsole -mcygwin -mno-cygwin -mdll
Xstormy16 Options -msim
Xtensa Options -mconst16 -mno-const16 -mfused-madd -mno-fused-madd
zSeries Options See S/390 and zSeries Options.
Code Generation Options
Options Controlling the Kind of Output
Options in file are separated by whitespace. A whitespace
Options Controlling C Dialect
Options Controlling C++ Dialect
Options Controlling Objective-C and Objective-C++ Dialects
Options to Control Diagnostic Messages Formatting
Options to Request or Suppress Warnings
For further language-specific options also refer to C++ Dialect Options
and Objective-C and Objective-C++ Dialect Options.
specificity, the last one takes effect. Options enabled or disabled via
Options and Objective-C and Objective-C++ Dialect Options.
Options for Debugging Your Program or GCC
Options That Control Optimization
Options of the form -fflag specify machine-independent flags. Most
Options Controlling the Preprocessor
Passing Options to the Assembler
Options for Linking
Options for Directory Search
AArch64 Options
Adapteva Epiphany Options
ARC Options
ARM Options
AVR Options
Blackfin Options
C6X Options
CRIS Options
CR16 Options
Darwin Options
DEC Alpha Options
FR30 Options
FRV Options
GNU/Linux Options
H8/300 Options
HPPA Options
IA-64 Options
LM32 Options
M32C Options
M32R/D Options
M680x0 Options
MCore Options
MeP Options
MicroBlaze Options
MIPS Options
MMIX Options
MN10300 Options
Moxie Options
MSP430 Options
NDS32 Options
Nios II Options
Nvidia PTX Options
PDP-11 Options
picoChip Options
PowerPC Options
RL78 Options
IBM RS/6000 and PowerPC Options
RX Options
S/390 and zSeries Options
Score Options
SH Options
Solaris 2 Options
SPARC Options
SPU Options
Options for System V
TILE-Gx Options
TILEPro Options
V850 Options
VAX Options
Visium Options
VMS Options
VxWorks Options
Options specific to the target hardware are listed with the other
x86 Options
x86 Windows Options
See also under x86 Options for standard options.
Xstormy16 Options
Xtensa Options
zSeries Options
Options for Code Generation Conventions
--
Regards,
Peng
