Hi Wolfgang,

On Mon, Mar 28, 2011 at 4:40 PM, Wolfgang Denk wd@denx.de wrote:

Commit 44c6e65 "rename _end to __bss_end__ broke building of a large number of systems (at least all PowerPC?):

libstubs.o: In function `app_startup': examples/standalone/stubs.c:197: undefined reference to `__bss_end__'

As a workaround (instead of introducing linker scripts) we can add a --defsym=__bss_end__=_end

Signed-off-by: Wolfgang Denk wd@denx.de Cc: Po-Yu Chuang ratbert@faraday-tech.com Cc: Albert Aribaud albert.aribaud@free.fr

---

What I really do not understand is why we don't see the same type of undefined reference errors on ARM?  ALso, on ARM we see __bss_end__ and _bss_end__, and __bss_start und __bss_start__ - where are the other names coming from? [On PPC we see only __bss_start and __bss_end__].

Do you mean _end here? If there is __bss_end__ on PPC, then there is no problem, right?

examples/standalone/Makefile |    1 +  1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/examples/standalone/Makefile b/examples/standalone/Makefile index c1dfdce..06cf14f 100644 --- a/examples/standalone/Makefile +++ b/examples/standalone/Makefile @@ -96,6 +96,7 @@ $(LIB):       $(obj).depend $(LIBOBJS)  $(ELF):  $(obj)%:       $(obj)%.o $(LIB)                $(LD) -g -Ttext $(STANDALONE_LOAD_ADDR) \

• --defsym=__bss_end__=_end \

-o $@ -e $(SYM_PREFIX)$(notdir $(<:.o=)) $< $(LIB) \                        -L$(gcclibdir) -lgcc

-- 1.7.4

---

U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot

Commit 44c6e65 "rename _end to __bss_end__ broke building of a large number of systems (at least all PowerPC?):

libstubs.o: In function `app_startup': examples/standalone/stubs.c:197: undefined reference to `__bss_end__'

The rename should not be done for the files in the examples/standalone/ directory, as these are not using the code from start.S, but do their own BSS clearing, and either use their own linker scripts or the ones provided by the compilers.

Signed-off-by: Wolfgang Denk wd@denx.de --- V2: Instead of messing with linker defines, revert the patch in question for the files in examples/standalone/ as suggested by Albert Aribaud. (Thanks!)

examples/standalone/mips.lds | 2 +- examples/standalone/sparc.lds | 2 +- examples/standalone/stubs.c | 4 ++-- 3 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/examples/standalone/mips.lds b/examples/standalone/mips.lds index 68ae217..63a1c92 100644 --- a/examples/standalone/mips.lds +++ b/examples/standalone/mips.lds @@ -55,5 +55,5 @@ SECTIONS .sbss (NOLOAD) : { *(.sbss) } .bss (NOLOAD) : { *(.bss) . = ALIGN(4); }

- __bss_end__ = .; + _end = .; } diff --git a/examples/standalone/sparc.lds b/examples/standalone/sparc.lds index 7f060b6..9733daa 100644 --- a/examples/standalone/sparc.lds +++ b/examples/standalone/sparc.lds @@ -57,5 +57,5 @@ SECTIONS } . = ALIGN(4); __bss_end = .; - __bss_end__ = .; + _end = .; } diff --git a/examples/standalone/stubs.c b/examples/standalone/stubs.c index 1379df7..2d2e709 100644 --- a/examples/standalone/stubs.c +++ b/examples/standalone/stubs.c @@ -187,14 +187,14 @@ void __attribute__((unused)) dummy(void) #include <_exports.h> }

-extern unsigned long __bss_start, __bss_end__; +extern unsigned long __bss_start, _end;

void app_startup(char * const *argv) { unsigned char * cp = (unsigned char *) &__bss_start;

/* Zero out BSS */ - while (cp < (unsigned char *)&__bss_end__) { + while (cp < (unsigned char *)&_end) { *cp++ = 0; }

From: Po-Yu Chuang ratbert@faraday-tech.com

It seems __bss_end__ is not a true convention for all toolchains, at least not for PPC. Using _end for standalone programs might be the simplest way to fix this problem.

One of the other choices may be writing a linker script to provide __bss_end__ for PPC.

Signed-off-by: Po-Yu Chuang ratbert@faraday-tech.com --- Hi all,

Not sure if this is the best solution, but I think this could fix Heiko's problem.

examples/standalone/mips.lds | 2 +- examples/standalone/sparc.lds | 2 +- examples/standalone/stubs.c | 4 ++-- 3 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/examples/standalone/mips.lds b/examples/standalone/mips.lds index 68ae217..63a1c92 100644 --- a/examples/standalone/mips.lds +++ b/examples/standalone/mips.lds @@ -55,5 +55,5 @@ SECTIONS .sbss (NOLOAD) : { *(.sbss) } .bss (NOLOAD) : { *(.bss) . = ALIGN(4); }

- __bss_end__ = .; + _end = .; } diff --git a/examples/standalone/sparc.lds b/examples/standalone/sparc.lds index 7f060b6..9733daa 100644 --- a/examples/standalone/sparc.lds +++ b/examples/standalone/sparc.lds @@ -57,5 +57,5 @@ SECTIONS } . = ALIGN(4); __bss_end = .; - __bss_end__ = .; + _end = .; } diff --git a/examples/standalone/stubs.c b/examples/standalone/stubs.c index 1379df7..2d2e709 100644 --- a/examples/standalone/stubs.c +++ b/examples/standalone/stubs.c @@ -187,14 +187,14 @@ void __attribute__((unused)) dummy(void) #include <_exports.h> }

-extern unsigned long __bss_start, __bss_end__; +extern unsigned long __bss_start, _end;

void app_startup(char * const *argv) { unsigned char * cp = (unsigned char *) &__bss_start;

/* Zero out BSS */ - while (cp < (unsigned char *)&__bss_end__) { + while (cp < (unsigned char *)&_end) { *cp++ = 0; }