Re: uint8_t SRAM variable for ATmega328p allocated at 0x060 (instead of 0x0100) in avr-gcc 4.6.2, 7.3.2

Senthil Kumar Selvaraj wrote:

> I don't see the problem when I tried compiling the below code with 4.6.2.
> Can you paste the command line you used, with -v and -Wl,--verbose turned on?
> It would be helpful to know what version of binutils was used, as well as the build steps.

Command used:

/usr/local/avr/bin/avr-gcc -I. \
    -D F_CPU=20000000UL \
    -g -mmcu=atmega328 -O1 \
    -fpack-struct \
    -fshort-enums \
    -funsigned-bitfields \
    -funsigned-char \
    -Wall \
    -ffunction-sections \
    -fdata-sections \
    -fno-exceptions \
    -Wa,-ahlms=obj/main.lst.gcc \
    -Wno-uninitialized \
    -c main.cpp -o obj/main.o

Here the result with -v -Wl,--verbose:

COLLECT_GCC=/usr/local/avr/bin/avr-gcc
Target: avr
Configured with: ../configure --prefix=/usr/local/avr --target=avr
--enable-languages=c,c++ --disable-nls --disable-libssp --with-dwarf2
Thread model: single
gcc version 4.7.3 (GCC)
COLLECT_GCC_OPTIONS='-I' '.' '-D' 'F_CPU=20000000UL' '-g'
'-mmcu=atmega328' '-O1' '-fpack-struct' '-fshort-enums'
'-funsigned-bitfields' '-funsigned-char' '-Wall' '-ffunction-sections'
'-fdata-sections' '-fno-exceptions' '-Wno-uninitialized' '-v' '-c'
'-o' 'obj/main.o'
 /usr/local/avr/libexec/gcc/avr/4.7.3/cc1plus.exe -quiet -v -I .
-imultilib avr5 -D F_CPU=20000000UL main.cpp -quiet -dumpbase main.cpp
-mmcu=atmega328 -auxbase-strip obj/main.o -g -O1 -Wall
-Wno-uninitialized -version -fpack-struct -fshort-enums
-funsigned-bitfields -funsigned-char -ffunction-sections
-fdata-sections -fno-exceptions -fno-rtti -fno-enforce-eh-specs
-fno-exceptions -o /tmp/ccFOZ1pq.s
GNU C++ (GCC) version 4.7.3 (avr)
        compiled by GNU C version 4.5.3, GMP version 4.3.2, MPFR
version 3.0.1-p4, MPC version 0.8
GGC heuristics: --param ggc-min-expand=100 --param ggc-min-heapsize=131072
ignoring nonexistent directory
"/usr/local/avr/lib/gcc/avr/4.7.3/../../../../avr/include/c++/4.7.3"
ignoring nonexistent directory
"/usr/local/avr/lib/gcc/avr/4.7.3/../../../../avr/include/c++/4.7.3/avr/avr5"
ignoring nonexistent directory
"/usr/local/avr/lib/gcc/avr/4.7.3/../../../../avr/include/c++/4.7.3/backward"
ignoring nonexistent directory
"/usr/local/avr/lib/gcc/avr/4.7.3/../../../../avr/sys-include"
#include "..." search starts here:
#include <...> search starts here:
 .
 /usr/local/avr/lib/gcc/avr/4.7.3/include
 /usr/local/avr/lib/gcc/avr/4.7.3/include-fixed
 /usr/local/avr/lib/gcc/avr/4.7.3/../../../../avr/include
End of search list.
GNU C++ (GCC) version 4.7.3 (avr)
        compiled by GNU C version 4.5.3, GMP version 4.3.2, MPFR
version 3.0.1-p4, MPC version 0.8
GGC heuristics: --param ggc-min-expand=100 --param ggc-min-heapsize=131072
Compiler executable checksum: 49d98612d3bd1e77bd63ccc498787f2f
COLLECT_GCC_OPTIONS='-I' '.' '-D' 'F_CPU=20000000UL' '-g'
'-mmcu=atmega328' '-O1' '-fpack-struct' '-fshort-enums'
'-funsigned-bitfields' '-funsigned-char' '-Wall' '-ffunction-sections'
'-fdata-sections' '-fno-exceptions' '-Wno-uninitialized' '-v' '-c'
'-o' 'obj/main.o'
 /usr/local/avr/lib/gcc/avr/4.7.3/../../../../avr/bin/as.exe
-mmcu=atmega328 -mno-skip-bug -ahlms=obj/main.lst.gcc -o obj/main.o
/tmp/ccFOZ1pq.s
COMPILER_PATH=/usr/local/avr/libexec/gcc/avr/4.7.3/:/usr/local/avr/libexec/gcc/avr/4.7.3/:/usr/local/avr/libexec/gcc/avr/:/usr/local/avr/lib/gcc/avr/4.7.3/:/usr/local/avr/lib/gcc/avr/:/usr/local/avr/lib/gcc/avr/4.7.3/../../../../avr/bin/
LIBRARY_PATH=/usr/local/avr/lib/gcc/avr/4.7.3/avr5/:/usr/local/avr/lib/gcc/avr/4.7.3/../../../../avr/lib/avr5/:/usr/local/avr/lib/gcc/avr/4.7.3/:/usr/local/avr/lib/gcc/avr/4.7.3/../../../../avr/lib/
COLLECT_GCC_OPTIONS='-I' '.' '-D' 'F_CPU=20000000UL' '-g'
'-mmcu=atmega328' '-O1' '-fpack-struct' '-fshort-enums'
'-funsigned-bitfields' '-funsigned-char' '-Wall' '-ffunction-sections'
'-fdata-sections' '-fno-exceptions' '-Wno-uninitialized' '-v' '-c'
'-o' 'obj/main.o'

The build steps is the command line above for compiling + link command:

/usr/local/avr/bin/avr-gcc
-Wl,--gc-sections,-Map,obj/testVolatile.elf.map  -mmcu=atmega328
/usr/local/avr/avr/lib/libm.a -o obj/testVolatile.elf
obj/main.o
-lm

Binutils:
$ ld -v
GNU ld (GNU Binutils) 2.23.52.20130309