1 # Misc library-related options
3 config CC_GCC_ENABLE_TARGET_OPTSPACE
5 prompt "Optimize gcc libs for size"
8 Pass --enable-target-optspace to crossgcc's configure.
10 This will compile crossgcc's libs with -Os.
12 config CC_GCC_USE_GRAPHITE
14 prompt "Enable GRAPHITE loop optimisations"
16 depends on CC_GCC_HAS_GRAPHITE
17 select CC_GCC_USE_PPL_CLOOG
19 Enable the GRAPHITE loop optimsations.
21 This requires the PPL and CLooG companion libraries, and
22 those will be automatically build for you.
24 On some systems (eg. Cygwin), PPL and/or CLooG may not
25 build properly (yet), so you'll have to say 'N' here.
27 # The way LTO works is a bit twisted.
28 # See: http://gcc.gnu.org/wiki/LinkTimeOptimization#Requirements
30 # - if binutils has plugins: LTO is handled by ld/gold by loading
31 # the plugin when linking
32 # - if binutils does not have plugins: LTO is handled by collect2
33 # In any case, LTO support does not depend on plugins, but takes
39 depends on CC_GCC_HAS_LTO
40 select CC_GCC_USE_LIBELF
42 Enable the Link Time Optimisations.
44 This will require the libelf companion library, and it
45 wil be build automatically for you.
47 config STATIC_TOOLCHAIN
48 select CC_STATIC_LIBSTDCXX if CC_GCC_4_4_or_later
50 config CC_STATIC_LIBSTDCXX
52 prompt "Link libstdc++ statically into the gcc binary"
54 depends on CC_GCC_4_4_or_later
56 Newer gcc versions use the PPL library which is C++ code. Statically
57 linking libstdc++ increases the likeliness that the gcc binary will
58 run on machines other than the one which it was built on, without
59 having to worry about distributing the matching version of libstdc++
62 config CC_GCC_LIBMUDFLAP
64 prompt "Compile libmudflap"
67 libmudflap is a pointer-use checking tool, which can detect
68 various mis-usages of pointers in C and (to some extents) C++.
70 You should say 'N' here, as libmduflap generates instrumented
71 code (thus it is a bit bigger and a bit slower) and requires
72 re-compilation and re-link, while it exists better run-time
73 alternatives (eg. DUMA, dmalloc...) that need neither re-
74 compilation nor re-link.
78 prompt "Compile libgomp"
81 libgomp is "the GNU implementation of the OpenMP Application Programming
82 Interface (API) for multi-platform shared-memory parallel programming in
83 C/C++ and Fortran". See:
84 http://gcc.gnu.org/onlinedocs/libgomp/
86 The default is 'N'. Say 'Y' if you need it, and report success/failure.
90 prompt "Compile libssp"
93 libssp is the run-time Stack-Smashing Protection library.
95 The default is 'N'. Say 'Y' if you need it, and report success/failure.
97 #-----------------------------------------------------------------------------
99 comment "Misc. obscure options."
103 prompt "Use __cxa_atexit"
105 depends on ! BARE_METAL
107 If you get the missing symbol "__cxa_atexit" when building C++ programs,
108 you might want to try disabling this option.
110 config CC_GCC_DISABLE_PCH
112 prompt "Do not build PCH"
115 Say 'y' here to not use Pre-Compiled Headers in the resulting toolchain.
116 at the expense of speed when compiling C++ code.
118 For some configurations (most notably canadian?), PCH are broken, and
119 need to be disabled. Please see:
120 http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40974
122 config CC_GCC_SJLJ_EXCEPTIONS
124 prompt "Use sjlj for exceptions"
125 depends on ! BARE_METAL
128 'sjlj' is short for setjmp/longjmp.
130 On some architectures, stack unwinding during exception handling
131 works perfectly well without using sjlj, while on some others,
132 use of sjlj is required for proper stack unwinding.
134 Option | sjlj use | Associated ./configure switch
135 ---------+--------------------+--------------------------------
136 Y | forcibly used | --enable-sjlj-exceptions
137 M | auto | (none, ./configure decides)
138 N | forcibly not used | --disable-sjlj-exceptions
140 It should be safe to say 'M' or 'N'.
142 It can happen that ./configure is wrong in some cases. Known
143 case is for ARM big endian, where you should say 'N'.
145 config CC_GCC_LDBL_128
147 prompt "Enable 128-bit long doubles"
149 depends on CC_GCC_4_2_or_later
151 Saying 'Y' will force gcc to use 128-bit wide long doubles
152 Saying 'N' will force gcc to use 64-bit wide long doubles
153 Saying 'M' will let gcc choose (default is 128-bit for
154 glibc >= 2.4, 64-bit otherwise)
156 If in doubt, keep the default, ie. 'M'.