arm-linux-gcc mcount_internal undefined reference error

[Byron Young <spamiccling at yahoo dot com>]

Building arm-linux glibc-2.3.3 on an
i386-redhat-linux(gcc-3.3.3) (FC2) system using a
custom built gcc-3.4.0 arm-linux cross compiler
terminates in:
gmon/mcount.c
undefined reference to `mcount_internal'
collect2: ld returned 1 exit status

After some adjustments, the error became a warning:
mcount.c:60: warning: 'mcount_internal' defined but
not used

To avoid the warning

if (0==1) mcount_internal(1,2);

was added to sysdeps/arm/machine-gmon.h #define MCOUNT
definition. With -O1, it was optimized out and did not
appear in the .s file.

Some attached source code (mod.c, mod.h, Makefile,
main.c) simulates this situation.

When compiling with ARM defined (make ARCH=ARM):
  -O2 reproduces the undefined reference error.
  -O1 reproduces the warning.
  -O1 AND if (0==1) gotohello(1,2); compiles with no
warning.

When compiling it with X86 defined (make ARCH=X86):
  -O[012] reproduces the warning.

Should the fact that the native gcc does not reproduce
the undefined reference error be a cause for concern?

Instead of if (0==1) gotohello(1,2) to avoid the
warning, is there a gcc extended asm construct that
will alert the compiler of a function reference?  The
following all fail: asm("blne mcount_internal;")
produces blne mcount_internal, without compiler noting
a function reference. asm("blne %0" : : "i"
(mcount_internal)); produces blne #mcount_internal,
which is not what is desired.

thanks,
Byron Young
spamiccling@yahoo.com

BEGIN main.c
int
main(int  argc, char * argv[], char * envp[]){
  return 0;
}
END main.c

BEGIN mod.c
#include "mod.h"

_GOTOHELLO_DECL(from, to)
{
  return;
}

HELLO

#ifdef  X86
int func1(int i) {
  register int _k asm("ebx")=0xF0F0F0F0;

  asm ("inc %0" : : "r"  (_k));
  //  asm ("jle %0" : : "i" (gotohello)); ERROR in
.s->.o
  //  asm ("jle %0" : : "s" (gotohello)); ERROR in
.s->.o
  asm ("inc %0" : : "r"  (_k));
  return 1;
}
#endif
#ifdef  ARM
int func1(int i) {
  register int _k asm("r3")=1234;

  asm("add %0,%1,#1" : "=g" (_k): "g" (_k));
  //  asm ("blne %0" : : "i" (gotohello)); ERROR in
.s->.o
  return _k;
}
#endif
END mod.c

BEGIN mod.h
void _hello(void);

#define weak_alias(name, aliasname) \
    extern __typeof(name) aliasname __attribute
((weak, alias (#name)));

weak_alias (_hello, hello)

static void gotohello(int from, int to);

#define _GOTOHELLO_DECL(from, to) \
   static void gotohello(int from, int to)

#ifdef ARM
#define HELLO								\
void _hello (void)							\
{									\
  __asm__("stmdb	sp!, {r0, r1, r2, r3};"				\
	  "movs		fp, fp;"				      	\
          "moveq	r1, #0;"					\
	  "ldrne	r1, [fp, $-4];"					\
	  "ldrne	r0, [fp, $-12];"				\
	  "movnes	r0, r0;"					\
	  "ldrne	r0, [r0, $-4];"					\
	  "movs		r0, r0;"					\
	  "blne		gotohello;"     				\
	  "ldmia	sp!, {r0, r1, r2, r3}");			\
  if (1==2) gotohello(1,2);                           
                 \
}
#endif

#ifdef X86
#define HELLO								\
void _hello (void)							\
{			                                                \
  __asm__("jle	gotohello;"                            
                \
          "nop;");                  	                	
\
  if (1==2) gotohello(1,2);                           
                 \
}
#endif
END mod.h

BEGIN Makefile
all:main

ifndef ARCH 
ARCH=ARM
endif

ifeq ($(ARCH),ARM)
else
  ifeq  ($(ARCH),X86)
  else
    ARCH=ARM
  endif
endif

ifeq ($(ARCH),ARM)
PATH:=/home/bkyoung/arm/bin:/home/bkyoung/arm/arm-linux/bin:$(PATH)
CC=arm-linux-gcc
else
  ifeq  ($(ARCH),X86)
CC=gcc
  endif
endif


CFLAGS=-O1 -D$(ARCH) -g -Wall -Wstrict-prototypes
-Wwrite-strings -fno-omit-frame-pointer

SOURCES=main.c mod.c
OBJS=$(SOURCES:.c=.o)
HEADERS=mod.h

main: $(SOURCES:.c=.o)
	$(CC)  $(CFLAGS) $^ -o $@

%.i : %.c $(HEADERS)  Makefile
	$(CC) $(CFLAGS) -E $< -o $@

%.s:  %.i
	$(CC) $(CFLAGS) -S $< -o $@

%.o: %.s
	$(CC) $(CFLAGS) -c $< -o $@

%.o : %.c

clean:
	$(RM) *~
	$(RM) *.o
	$(RM) main
	$(RM) *.i
	$(RM) *.s

SECONDARY:$(SOURCES:.c=.i) $(SOURCES:.c=.s)
$(SOURCES:.c=.o)

edit:
	emacs $(SOURCES:.c=.i) $(SOURCES:.c=.s) $(SOURCES)
$(HEADERS) Makefile
END Makefile

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