i686-w64-mingw32-c++ compile with debug option on - debugging

I'm trying to compile a really simple program with "i686-w64-mingw32-c++" and I tried to add the "-debug" flag but nothing changed.
How can I compile with debug information?

The flag you need is compiler -g. This will add debugging information.
When linking you should also make sure you don't strip the debugging information (make sure the linker flag -s is not used).
To see the full help use -v --help flags.

Related

Getting a segmentation fault when trying to build my GCC backend

I am currently trying to write a GCC backend for a new architecture, but when I try to compile it I get the following error message:
xgcc: internal compiler error: Segmentation fault signal terminated program cc1
The build is configured with the following command:
../gcc/configure --prefix=--prefix=$HOME/GCC-10.0.1 --disable-bootstrap --target=arch_name --enable-languages=c
How would I go about fixing this error so that I can build my backend?
As far as I am aware, I have implemented the target macro's, functions and insn patterns required to get GCC to build.
Sorry that the question is a bit vague, I am not sure what extra information I can provide. If more specific information is needed please let me know and I will edit the question.
Thanks in advance.
How would I go about fixing this error so that I can build my backend?
Debug cc1.
xgcc is located in $builddir/gcc. Hence run $builddir/xgcc -B$builddir -v -save-temps <options-that-crash-cc1>.
xgcc -v ... will print the sub-commands it is calling, record the options it supplies to the crashing cc1 call.
Run a debugger against that cc1 call, supply the right options and put a breakpoint at abort (will be fancy_abort) actually.
Build the compiler without optimization. It's enough to run make in $builddir/gcc for that. You can supply additional option if you like, e.g. make -j4 cc1 CXXFLAGS='<flags-to-pass>'.
$builddir/gcc provides .gdbinit to augment gdb with additional hooks to improve debugging experience.

How can I suppress assembly files output by compilation proper?

I have some C++ library code that I want strictly compiled for a quick check, and I don't want any files produced to be used for later stages (assembly, linkage, etc.)
I can do
g++ -S main.cpp
but this will give me an assembly file that I'm just going to wind up deleting anyway.
Is there an option that will tell the compiler to just compile a source file but don't produce any files?
EDIT[0]: I'm using mingw on Windows.
gcc has the option -fsyntax-only:
Check the code for syntax errors, but don’t do anything beyond that.

Correct GCC compile command for building exe (to use with gdb)

I have a file called val_ref.c and I compiled it using the command flag:
gcc val_ref.c -DDEBUG
after that, I opened gdb using the following command:
gdb a % the resulting execuatable is called a
Then I used the following commands to set breakpoints and run the debugger:
(gdb) break main
(gdb) break incvar
(gdb) run
(gdb) continue
However, I cannot see the line-by-line proceeding information on the console. Instead, I see this:
I am not sure what I am doing wrong. For example, if I was to build this as a console application in VS2010 or Eclipse Kepler (with MinGW toolchain), and then run gdb on the exec, it will work perfect, (I think). Seems like I am not adding the correct directives/flags in my compile. Can anybody help me with it?
How about the -g flag? This the usual flag for gdb..
The best flags to use to compile for debugging are -g and -O0. -g causes GCC to add debugging information to the executable, and -O0 stops GCC enabling optimizations which would be confusing when debugging.

Disable warnings being treated as errors (cc1.exe)

I am developing a BREW application. When compiling the application to get a MOD file, I am continuously getting this error:
cc1.exe: warnings being treated as errors
I want to disable this warning. I have googled it, and many say disabling -werror will help, but how can I do that?
The compiler is CodeSourcery ARM.
You need to remove -Werror from CFLAGS, CPPFLAGS etc.; these are usually set in Makefile's or build scripts.
However, I'd strongly advice to fix the actual warnings instead, which will produce more stable and error-free code.
Run this Command in Terminal to say, not to consider warning as error
make CFLAGS="-Wno-error=format-truncation"

Creating debug build of autotools' build source

Given:
source tar.gz
AFAIK, configure does support debug build (configure --help doesn't show --enable-debug)
Questions:
Is it safe to use debug build if the authors of the package didn't supplied it in the first place?
If the answer to pre.v question is yes, than how I can produce debug build? Should I patch configure.ac?
Thanks
A properly crafted Autotools project supports user-supplied compiler and linker flags. Some authors choose to provide --enable-debug to simplify creation of debug builds, but its absence does not mean it cannot be done. The first thing I recommend you try is to specify compiler and linker flags that are suitable to your debugging needs. If you are using gcc on Linux, that could be
./configure CFLAGS="-ggdb3 -O0" CXXFLAGS="-ggdb3 -O0" LDFLAGS="-ggdb3"
It is recommended to specify the variables as parameters to configure, as shown, instead of as environment variables. By doing it this way, the Autotools will keep these settings when you make changes that trigger an automatic reconfiguration.
If that does not produce the desired result, yes, hacking the build system may be necessary.
You could define an alias that automatically sets the environment variables:
alias configuredebug='CPPFLAGS=-DDEBUG CFLAGS="-g -O0" CXXFLAGS="-g -O0" ./configure'

Resources