add --enable-debug for configure #3792

./configure --debug-enable will create a "debug" build, with all debug symbols and no optimizations.

ACK

Edit: are you sure that this will work at all? You're setting the debug flags in the top-level Makefile.am. I don't think these flags are actually used anywhere?

Mesa implements it the following way, which I think is better as it requires no changes to the Makefile.ams:

AC_ARG_ENABLE([debug],
    [AS_HELP_STRING([--enable-debug],
        [use debug compiler flags and macros @<:@default=disabled@:>@])],
    [enable_debug="$enableval"],
    [enable_debug=no]
)
if test "x$enable_debug" = xyes; then
    DEFINES="$DEFINES -DDEBUG"
    if test "x$GCC" = xyes; then
        CFLAGS="$CFLAGS -g -O0"
    fi
    if test "x$GXX" = xyes; then
        CXXFLAGS="$CXXFLAGS -g -O0"
    fi
fi

-ggdb preferred over -g when supported ;)

-ggdb implies -g3? I lost track of all the debug options, though for C++ it's essential to use the right ones because it can be pretty hellish to debug otherwise.

The lannwj's change it more graceful, better compatibility.

-ggdb3 including GDB extensions if at all possible. -g3 not I think the -ggdb3 is shoulb be best support for GDB, but for support more debugger, we should use -g3. For debug options details please see http://gcc.gnu.org/onlinedocs/gcc-4.3.3/gcc/Debugging-Options.html#Debugging-Options

And the DEFINES="$DEFINES -DDEBUG" seems not work, so I add the -DDEBUG to CFLAGS too.

So how about like this?

AC_PROG_CXX
AC_PROG_CC
...

# Enable debug, the CFLAG="-g -O2" in here
AC_ARG_ENABLE([debug],
    [AS_HELP_STRING([--enable-debug],
                    [use debug compiler flags and macros (default is no)])],
    [enable_debug=$enableval],
    [enable_debug=no])

if test "x$enable_debug" = xyes; then
    if test "x$GCC" = xyes; then
        CFLAGS="-g3 -O0 -DDEBUG"
    fi
    if test "x$GXX" = xyes; then
        CXXFLAGS="-g3 -O0 -DDEBUG"
    fi
fi 

Automatic sanity-testing: PASSED, see http://jenkins.bluematt.me/pull-tester/ae3c8ffede4d8ef04932eeac238fb4ca14ae0057 for binaries and test log. This test script verifies pulls every time they are updated. It, however, dies sometimes and fails to test properly. If you are waiting on a test, please check timestamps to verify that the test.log is moving at http://jenkins.bluematt.me/pull-tester/current/ Contact BlueMatt on freenode if something looks broken.

Tested, and works fine for me.

With --enable-debug:

g++ -DHAVE_CONFIG_H -I. -pthread     -pthread     -I../src/obj  -pthread -I/usr/include  -I../src/leveldb/include -I../src/leveldb/helpers/memenv -I.  
 -DBOOST_SPIRIT_THREADSAFE -DHAVE_BUILD_INFO -D__STDC_FORMAT_MACROS  -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=2 
 -g3 -O0 -DDEBUG 
 -Wall -Wextra -Wformat -Wformat-security -Wno-unused-parameter  -Wstack-protector -fstack-protector-all -fPIE -MT alert.o -MD -MP -MF $depbase.Tpo -c -o alert.o alert.cpp &&\

Without --enable-debug:

g++ -DHAVE_CONFIG_H -I. -pthread     -pthread     -I../src/obj  -pthread -I/usr/include  -I../src/leveldb/include -I../src/leveldb/helpers/memenv -I. 
 -DBOOST_SPIRIT_THREADSAFE -DHAVE_BUILD_INFO -D__STDC_FORMAT_MACROS     -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=2 
 -g -O2 
 -Wall -Wextra -Wformat -Wformat-security -Wno-unused-parameter  -Wstack-protector -fstack-protector-all -fPIE -MT addrman.o -MD -MP -MF $depbase.Tpo -c -o addrman.o addrman.cpp &&\

Please squash this change into one commit, then I'll merge.

resent to #3833