Custom Version back-tracking on a each object.

Hi, im not understand this post http://www.linuxjournal.com/content/add-auto-incrementing-build-number-your-build-process#comment-356616[^].
I try to implement some object version status such as git info (last commit and author), build time, date and number.

I dont have any skill in assembler, but this does not work fine.
Can you anyone say me how this work at program level?

Why assembler say warnings like:

/tmp/cccGQytx.s: Assembler messages:
/tmp/cccGQytx.s:3: Warning: entity size for SHF_MERGE not specified
/tmp/cccGQytx.s:3: Warning: group name for SHF_GROUP not specified

version.h

#include <string>
#include <time.h>

#define PUT_VERSION_INFO(args...) \
    asm("  .section .build_info, \"d\"\n"); \
    static const struct core::Version_t::build_info_t build_info = {__FILE__, __DATE__, __TIME__, ## args}; \
    asm("  .data\n")

#define GET_VERSIONS() \
    static const struct core::Version_t::build_info_t* _build_info = (struct core::Version_t::build_info_t*) &build_info
    
namespace core {
    class Version_t {
        private:
            time_t  m_buildtime;
            int     m_buildNumber;
        public:
            struct build_info_t {
                char*   m_filename;
                std::string m_date;
                std::string m_time;
                std::string m_author;
                std::string m_change;
            };
            Version_t();
            std::string getBuildTime();
            int getBuildNumber();
            virtual ~Version_t();
    };
};

version.cc

namespace core {
    Version_t::Version_t() { };
    std::string Version_t::getBuildTime() {
        return "xxx  ";
    };
    int Version_t::getBuildNumber() {
        return 0;
    };
    Version_t::~Version_t() { };
    asm("  .section .build_info, \"d\"\n");
    static const struct Version_t::build_info_t build_info = {__FILE__, __DATE__, "", "", ""};
    asm("  .data\n");
};

main.cc

#include <iostream>
#include "version.h"
//namespace core {
    asm("  .section .build_info, \"d\"\n");
    static const struct core::Version_t::build_info_t build_info = {__FILE__, __DATE__, "", "", ""};
    asm("  .data\n");
//};
int main() {
    core::Version_t v;
    //extern const char           __build_info;
    //namespace core {
    //struct core::Version_t::build_info_t* bstruct = (struct core::Version_t::build_info_t*) &build_info;
    //asm("  .section .build_info, \"d\"\n");
    struct core::Version_t::build_info_t* bstruct = (struct core::Version_t::build_info_t*) &build_info;
    //asm("  .data\n");
    //struct Version_t::build_info_t  binfo;// = (struct Version_t::build_info_t*) &__build_info;
    //};
    while(bstruct->m_filename) {
        std::cout << bstruct->m_filename << std::endl;
        bstruct++;
    };
    return 0;
};

Makefile

BINARY_name = libpagi
OBJFILES := $(patsubst %.cc,%.o,$(wildcard *.cc))
.PHONY: all
all: $(BINARY_name)
$(BINARY_name): $(OBJFILES)
    $(CXX) -g -Wall -o $(BINARY_name) $(LIBRARY_DIR) $(INCLUDE_DIR) $(LIBS) $(OBJFILES)
    @echo "Project '$(BINARY_name)' builded!"
%.o: %.cc
    $(shell git log $(shell basename $@ .o).cc | cut -d' ' -f 2 | tr -s [:space:] | sed -e '{:q;N;s/\n/", "/g;t q};' > temp)
#@sed -i "s/PUT_VERSION_INFO([^;]*;/PUT_VERSION_INFO(\"`cat temp`\");/gi" $(shell basename $@ .o).cc
    @echo "Build new version of module: $@ -> $(shell cat temp)."
    @rm temp
    $(CXX) -Wall -c -o $@ $<
clean:
    rm $(BINARY_name)* *.o

Compilation output:

Build new version of module: main.o -> 1f671ad6311f89860947f0b0b42aee5444b468d9, gimper.
g++ -Wall -c -o main.o main.cc
main.cc:7: warning: deprecated conversion from string constant to ‘char*’
main.cc: In function ‘int main()’:
main.cc:13: warning: unused variable ‘__build_info’
/tmp/ccVnldjr.s: Assembler messages:
/tmp/ccVnldjr.s:5: Warning: entity size for SHF_MERGE not specified
/tmp/ccVnldjr.s:5: Warning: group name for SHF_GROUP not specified
as: main.o: warning: sh_link not set for section `.build_info'
Build new version of module: version.o -> 1f671ad6311f89860947f0b0b42aee5444b468d9, gimper.
g++ -Wall -c -o version.o version.cc
version.cc:6: warning: deprecated conversion from string constant to ‘char*’
/tmp/ccN7FXjD.s: Assembler messages:
/tmp/ccN7FXjD.s:3: Warning: entity size for SHF_MERGE not specified
/tmp/ccN7FXjD.s:3: Warning: group name for SHF_GROUP not specified
as: version.o: warning: sh_link not set for section `.build_info'
g++ -g -Wall -o libpagi    main.o version.o
/usr/bin/ld: main.o: warning: sh_link not set for section `.build_info'
/usr/bin/ld: version.o: warning: sh_link not set for section `.build_info'
Project 'libpagi' builded!

Program output:

main.cc
Neoprávněný přístup do paměti (SIGSEGV)

Code isnt complete, macros lost.

Can anybody help me with this?
Thanx a lot.

Tags: C++, Linux