How to request -mthumb to be applied to all tools built for arm
Yann E. MORIN
yann.morin.1998@anciens.enib.fr
Wed Jan 6 20:08:00 GMT 2010
Lev, All,
On Wednesday 06 January 2010 14:39:02 lev@lingnu.com wrote:
> I am withdrawing my question about making -mthumb default compilation
> option, and here comes the the question - how to specify
> compilation/configuration options to the tools which are a part of
> toolchain,
It's seldom used, but you have:
CT_TARGET_CFLAGS
CT_TARGET_LDFLAGS
> Suppose I want to build libstc++ using -mthumb, how can this be achieved ?
> I was trying to change manually Makefile.am in the
> targets/src/gcc-4.4.1/libstdc++-v3/src/Makefile.am but it does not copied
> the -mthumb to the generated Makefile in the build area.
And for the special case gcc is, the following variable is indeed used
to build libstdc++:
CT_CC_ENABLE_CXX_FLAGS
> > I know the guys at ARM managed to build a Linux kernel using pure Thumb2,
> > and that it's now mainline, but so far I have not seen any 'Linux' libc
> > build in pure Thumb mode.
> I am not sure , -mthumb produced Thumb2 assembly ?
Base on the correct processor passed as -mcpu, yes, -mthumb will generate
proper Thumb2 insns. Eg. if you pass: -mcpu=cortex-m3 -mthumb
Thumb2 is just plain Thumb, plus a few other insns, but hose new ones
will probably be used only in a kernel (eg. interrupt handling...). But
I'm no Thumb2 expert... :-/
Regards,
Yann E. MORIN.
--
.-----------------.--------------------.------------------.--------------------.
| Yann E. MORIN | Real-Time Embedded | /"\ ASCII RIBBON | Erics' conspiracy: |
| +33 662 376 056 | Software Designer | \ / CAMPAIGN | ___ |
| +33 223 225 172 `------------.-------: X AGAINST | \e/ There is no |
| http://ymorin.is-a-geek.org/ | _/*\_ | / \ HTML MAIL | v conspiracy. |
`------------------------------^-------^------------------^--------------------'
--
For unsubscribe information see http://sourceware.org/lists.html#faq
More information about the crossgcc
mailing list