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2010-07-04Make sure that argv[] argument pointers are not modified.Wolfgang Denk
The hush shell dynamically allocates (and re-allocates) memory for the argument strings in the "char *argv[]" argument vector passed to commands. Any code that modifies these pointers will cause serious corruption of the malloc data structures and crash U-Boot, so make sure the compiler can check that no such modifications are being done by changing the code into "char * const argv[]". This modification is the result of debugging a strange crash caused after adding a new command, which used the following argument processing code which has been working perfectly fine in all Unix systems since version 6 - but not so in U-Boot: int main (int argc, char **argv) { while (--argc > 0 && **++argv == '-') { /* ====> */ while (*++*argv) { switch (**argv) { case 'd': debug++; break; ... default: usage (); } } } ... } The line marked "====>" will corrupt the malloc data structures and usually cause U-Boot to crash when the next command gets executed by the shell. With the modification, the compiler will prevent this with an error: increment of read-only location '*argv' N.B.: The code above can be trivially rewritten like this: while (--argc > 0 && **++argv == '-') { char *arg = *argv; while (*++arg) { switch (*arg) { ... Signed-off-by: Wolfgang Denk <wd@denx.de> Acked-by: Mike Frysinger <vapier@gentoo.org>
2010-05-28nios2: fix r15 issue for gcc4Thomas Chou
The "-ffixed-r15" option doesn't work well for gcc4. Since we don't use gp for small data with option "-G0", we can use gp as global data pointer. This allows compiler to use r15. It is necessary for gcc4 to work properly. Signed-off-by: Thomas Chou <thomas@wytron.com.tw> Signed-off-by: Scott McNutt <smcnutt@psyent.com>
2009-09-02Blackfin: change global data register from P5 to P3Robin Getz
Since the Blackfin ABI favors higher scratch registers by default, use the last scratch register (P3) for global data rather than the first (P5). This allows the compiler's register allocator to use higher number scratch P registers, which in turn better matches the Blackfin instruction set, which reduces the size of U-Boot by more than 1024 bytes... Signed-off-by: Robin Getz <robin.getz@analog.com> Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2008-02-15Merge branch 'master' of git://www.denx.de/git/u-boot-blackfinWolfgang Denk
Conflicts: Makefile doc/README.standalone Signed-off-by: Wolfgang Denk <wd@denx.de>
2008-02-14PPC: Use r2 instead of r29 as global data pointerWolfgang Denk
R29 was an unlucky choice as with recent toolchains (gcc-4.2.x) gcc will refuse to use load/store multiple insns; instead, it issues a list of simple load/store instructions upon function entry and exit, resulting in bigger code size, which in turn makes the build for a few boards fail. Use r2 instead. Signed-off-by: Wolfgang Denk <wd@denx.de>
2008-02-04add some more Blackfin docsMike Frysinger
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2003-07-26* Allow crc32 to be used at address 0x000wdenk
* Provide consistent interface to standalone applications to access the 'global_data' structure Provide a doc/README.standalone more useful to users/developers. * Make IceCube MGT5100 FEC driver work
2003-07-24* Implement new mechanism to export U-Boot's functions to standalonewdenk
applications: instead of using (PPC-specific) system calls we now use a jump table; please see doc/README.standalone for details * Patch by Dave Westwood, 24 Jul 2003: added support for Unity OS (a proprietary OS)