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AR# 22159

7.1i SP2 - EDK/GNU-/..../demangle.c(.text+0x23b0): undefined reference to `realloc'


Keywords: realloc, link, C++, MicroBlaze

Urgency: Standard

General Description:
When I try to compile a c++ application with the MicroBlaze compiler, I receive linker errors (unresolved symbols), not traceable to my source code. It makes no difference whether I run the compiler/linker from within the EDK, or from within the Xygwin shell.

Error Message:
mb-gcc -O2 test/*.cpp -o test/executable.elf \
-mno-xl-soft-mul -mno-xl-soft-div -mhard-float -Wl,-T -Wl,test_linker_script -g -I./microblaze_0/include/ -Itest/ -L./microblaze_0/lib/ \
-xl-mode-executable \

/cygdrive/c/cae/Xilinx/Edk7.1/gnu/microblaze/nt/bin/../lib/gcc/microblaze/3.4.1/../../../../microblaze/lib/libstdc++.a(cp-demangle.o): In function `d_print_resize':
/cygdrive/y/gnu_builds/halite/env/Jobs/MDT/sw/nt/gnu1/bld_mb_gcc/microblaze/libstdc++-v3/libsupc++/cp-demangle.c(.text+0x23b0): undefined reference to `realloc'
./microblaze_0/lib//libc.a(malloc.o): In function `malloc':
malloc.o(.text+0x8): relocation truncated to fit: R_MICROBLAZE_SRW32 .sdata
malloc.o(.text+0x20): relocation truncated to fit: R_MICROBLAZE_SRW32 .sdata
collect2: ld returned 1 exit status
make: *** [test/executable.elf] Error 1


Create a file called "realloc.c" with the following contents:

#include <stdlib.h>
void *realloc (void *ptr, size_t size)
return NULL;

Include "realloc.c" as a part of your sources. It is just a dummy implementation and should get rid of the compile issue.

The issue will be resolved in the future major release of the software.
AR# 22159
Date Created 10/04/2005
Last Updated 04/16/2007
Status Archive
Type General Article