debugging with Go using gdb

["paul@wrada.com" <pa...@wrada.com>]

Just thought I'd share my debug experience with the newt tool using gdb.

First, if you are a OS developer, you are probably not messing with newt so there isn't much use for this tutorial; you may want to ignore this. But if you are changing the newt or newtmgr code, this may be helpful.

You must build your go code with the following options... to tell go to add debug symbols.


go build -gcflags "-N -l"


Then you can run the debugger on the code. Do this from your mynewt project folder:

$gdb newt

You should see this in the gdb startup:


Reading symbols from /Users/paulfdietrich/Development/Go/bin/newt...done.

Loading Go Runtime support.


Once this happens, GDB automatically uses the goenv to set source paths etc so this should not be a problem.


You run the program just like you would with gdb in other languages


(gdb) run -l DEBUG -v build app


Settings breakpoints is a bit trickier than with C since the namespaces are required.

To break in main, use

(gdb)b main.main

You must use the fully qualified namespace and function. So for apache my newt's newt tool, use something like this

(gdb)b mynewt.apache.org/newt/newt/builder.NewTargetBuilder

If you have a function with a receiver, you can just add it to the name like this with more dots in the namespace

(gdb)b mynewt.apache.org/newt/newt/builder.(*TargetBuilder).Build


Happy Debugging!!!

NOTE: I almost got all of this to work within LiteIDE except that I could not tell it how to run the program from project directory of my mynewt project, so I could not get it to find the project.yml files.  Anyone know how to set that stuff in LiteIDE.

Paul

Re: debugging with Go using gdb

["paul@wrada.com" <pa...@wrada.com>]

Sorry Šone correction.

When you launch GDB from your mynewt project folder, you have to give it
the full path to newt

$gdb $GOPATH/bin/newt




On 7/1/16, 4:37 PM, "paul@wrada.com" <pa...@wrada.com> wrote:

>
>Just thought I'd share my debug experience with the newt tool using gdb.
>
>First, if you are a OS developer, you are probably not messing with newt
>so there isn't much use for this tutorial; you may want to ignore this.
>But if you are changing the newt or newtmgr code, this may be helpful.
>
>You must build your go code with the following options... to tell go to
>add debug symbols.
>
>
>go build -gcflags "-N -l"
>
>
>Then you can run the debugger on the code. Do this from your mynewt
>project folder:
>
>$gdb newt
>
>You should see this in the gdb startup:
>
>
>Reading symbols from /Users/paulfdietrich/Development/Go/bin/newt...done.
>
>Loading Go Runtime support.
>
>
>Once this happens, GDB automatically uses the goenv to set source paths
>etc so this should not be a problem.
>
>
>You run the program just like you would with gdb in other languages
>
>
>(gdb) run -l DEBUG -v build app
>
>
>Settings breakpoints is a bit trickier than with C since the namespaces
>are required.
>
>To break in main, use
>
>(gdb)b main.main
>
>You must use the fully qualified namespace and function. So for apache my
>newt's newt tool, use something like this
>
>(gdb)b mynewt.apache.org/newt/newt/builder.NewTargetBuilder
>
>If you have a function with a receiver, you can just add it to the name
>like this with more dots in the namespace
>
>(gdb)b mynewt.apache.org/newt/newt/builder.(*TargetBuilder).Build
>
>
>Happy Debugging!!!
>
>NOTE: I almost got all of this to work within LiteIDE except that I could
>not tell it how to run the program from project directory of my mynewt
>project, so I could not get it to find the project.yml files.  Anyone
>know how to set that stuff in LiteIDE.
>
>Paul
>
>
>
>