Testfile

1.39 2005-06-06 Sample Chapter 1

Sample Section 1

Some text. Some more text.

Sample Section 2

Some bold text and emphasised.

Introduction

Preface

One of the factors that delay a bug being fixed is the way it is reported. By creating this guide, we hope to help improve the communication between developers and users in bug resolution. Getting bugs fixed is an important, if not crucial part of the quality assurance for any project and hopefully this guide will help make that a success.

Bugs!!!!

You're emerge-ing a package or working with a program and suddenly the worst happens -- you find a bug. Bugs come in many forms like emerge failures or segmentation faults. Whatever the cause, the fact still remains that such a bug must be fixed. Here is a few examples of such bugs.

$ ./bad_code `perl -e 'print Ax100'`
Segmentation fault

/usr/lib/gcc-lib/i686-pc-linux-gnu/3.3.2/include/g++-v3/backward/backward_warning.h:32:2:
warning: #warning This file includes at least one deprecated or antiquated
header. Please consider using one of the 32 headers found in section 17.4.1.2 of
the C++ standard. Examples include substituting the <X> header for the <X.h>
header for C++ includes, or <sstream> instead of the deprecated header
<strstream.h>. To disable this warning use -Wno-deprecated.
In file included from main.cc:40:
menudef.h:55: error: brace-enclosed initializer used to initialize `
OXPopupMenu*'
menudef.h:62: error: brace-enclosed initializer used to initialize `
OXPopupMenu*'
menudef.h:70: error: brace-enclosed initializer used to initialize `
OXPopupMenu*'
menudef.h:78: error: brace-enclosed initializer used to initialize `
OXPopupMenu*'
main.cc: In member function `void OXMain::DoOpen()':
main.cc:323: warning: unused variable `FILE*fp'
main.cc: In member function `void OXMain::DoSave(char*)':
main.cc:337: warning: unused variable `FILE*fp'
make[1]: *** [main.o] Error 1
make[1]: Leaving directory
`/var/tmp/portage/xclass-0.7.4/work/xclass-0.7.4/example-app'
make: *** [shared] Error 2

!!! ERROR: x11-libs/xclass-0.7.4 failed.
!!! Function src_compile, Line 29, Exitcode 2
!!! 'emake shared' failed

These errors can be quite troublesome. However, once you find them, what do you do? The following sections will look at two important tools for handling run time errors. After that, we'll take a look at compile errors, and how to handle them. Let's start out with the first tool for debugging run time errors -- gdb.

Debugging using GDB

Introduction

GDB, or the (G)NU (D)e(B)ugger, is a program used to find run time errors that normally involve memory corruption. First off, let's take a look at what debugging entails. One of the main things you must do in order to debug a program is to emerge the program with FEATURES="nostrip". This prevents the stripping of debug symbols. Why are programs stripped by default? The reason is the same as that for having gzipped man pages -- saving space. Here's how the size of a program varies with and without debug symbol stripping.

(debug symbols stripped)
-rwxr-xr-x  1 chris users 3140  6/28 13:11 bad_code
(debug symbols intact)
-rwxr-xr-x  1 chris users 6374  6/28 13:10 bad_code

Just for reference, bad_code is the program we'll be debugging with gdb later on. As you can see, the program without debugging symbols is 3140 bytes, while the program with them is 6374 bytes. That's close to double the size! Two more things can be done for debugging. The first is adding ggdb3 to your CFLAGS and CXXFLAGS. This flag adds more debugging information than is generally included. We'll see what that means later on. This is how /etc/make.conf might look with the newly added flags.

CFLAGS="-O1 -pipe -g -ggdb"
CXXFLAGS="${CFLAGS}"

Lastly, you can also add debug to the package's USE flags. This can be done with the package.use file.

# echo "category/package debug" >> /etc/portage/package.use

The directory /etc/portage does not exist by default and you may have to create it, if you have not already done so. If the package already has USE flags set in package.use, you will need to manually modify them in your favorite editor.

Then we re-emerge the package with the modifications we've done so far as shown below.

# FEATURES="nostrip" emerge package

Now that debug symbols are setup, we can continue with debugging the program.

Running the program with GDB

Let's say we have a program here called "bad_code". Some person claims that the program crashes and provides an example. You go ahead and test it out:

$ ./bad_code `perl -e 'print Ax100'`
Segmentation fault

It seems this person was right. Since the program is obviously broken, we have a bug at hand. Now, it's time to use gdb to help solve this matter. First we run gdb with --args, then give it the full program with arguments like shown:

$ gdb --args ./bad_code `perl -e 'print Ax100'`
GNU gdb 6.3
Copyright 2004 Free Software Foundation, Inc.
GDB is free software, covered by the GNU General Public License, and you are
welcome to change it and/or distribute copies of it under certain conditions.
Type "show copying" to see the conditions.
There is absolutely no warranty for GDB. Type "show warranty" for details.
This GDB was configured as "i686-pc-linux-gnu"...Using host libthread_db library "/lib/libthread_db.so.1".

One can also debug with core dumps. These core files contain the same information that the program would produce when run with gdb. In order to debug with a core file with bad_code, you would run gdb ./bad_code core where core is the name of the core file.

You should see a prompt that says "(gdb)" and waits for input. First, we have to run the program. We type in run at the command and receive a notice like:

(gdb) run
Starting program: /home/chris/bad_code

Program received signal SIGSEGV, Segmentation fault.
0xb7ec6dc0 in strcpy () from /lib/libc.so.6

Here we see the program starting, as well as a notification of SIGSEGV, or Segmentation Fault. This is GDB telling us that our program has crashed. It also gives the last run function it could trace when the program crashes. However, this isn't too useful, as there could be multiple strcpy's in the program, making it hard for developers to find which one is causing the issue. In order to help them out, we do what's called a backtrace. A backtrace runs backwards through all the functions that occurred upon program execution, to the function at fault. Functions that return (without causing a crash) will not show up on the backtrace. To get a backtrace, at the (gdb) prompt, type in bt. You will get something like this:

(gdb) bt
#0  0xb7ec6dc0 in strcpy () from /lib/libc.so.6
#1  0x0804838c in run_it ()
#2  0x080483ba in main ()

You can notice the trace pattern clearly. main() is called first, followed by run_it(), and somewhere in run_it() lies the strcpy() at fault. Things such as this help developers narrow down problems. There are a few exceptions to the output. First off is forgetting to enable debug symbols with FEATURES="nostrip". With debug symbols stripped, the output looks something like this:

(gdb) bt
#0  0xb7e2cdc0 in strcpy () from /lib/libc.so.6
#1  0x0804838c in ?? ()
#2  0xbfd19510 in ?? ()
#3  0x00000000 in ?? ()
#4  0x00000000 in ?? ()
#5  0xb7eef148 in libgcc_s_personality () from /lib/libc.so.6
#6  0x080482ed in ?? ()
#7  0x080495b0 in ?? ()
#8  0xbfd19528 in ?? ()
#9  0xb7dd73b8 in __guard_setup () from /lib/libc.so.6
#10 0xb7dd742d in __guard_setup () from /lib/libc.so.6
#11 0x00000006 in ?? ()
#12 0xbfd19548 in ?? ()
#13 0x080483ba in ?? ()
#14 0x00000000 in ?? ()
#15 0x00000000 in ?? ()
#16 0xb7deebcc in __new_exitfn () from /lib/libc.so.6
#17 0x00000000 in ?? ()
#18 0xbfd19560 in ?? ()
#19 0xb7ef017c in nullserv () from /lib/libc.so.6
#20 0xb7dd6f37 in __libc_start_main () from /lib/libc.so.6
#21 0x00000001 in ?? ()
#22 0xbfd195d4 in ?? ()
#23 0xbfd195dc in ?? ()
#24 0x08048201 in ?? ()

This backtrace contains a large number of ?? marks. This is because without debug symbols, gdb doesn't know how the program was run. Hence, it is crucial that debug symbols are not stripped. Now remember a while ago we mentioned the -ggdb flag. Let's see what the output looks like with the flag enabled:

(gdb) bt
#0  0xb7e4bdc0 in strcpy () from /lib/libc.so.6
#1  0x0804838c in run_it (input=0x0) at bad_code.c:7
#2  0x080483ba in main (argc=1, argv=0xbfd3a434) at bad_code.c:12

Here we see that a lot more information is available for developers. Not only is function information displayed, but even the exact line numbers of the source files. This method is the most preferred if you can spare the extra space. Here's how much the file size varies between debug, strip, and -ggdb enabled programs.

(debug symbols stripped)
-rwxr-xr-x  1 chris users 3140  6/28 13:11 bad_code
(debug symbols enabled)
-rwxr-xr-x  1 chris users 6374  6/28 13:10 bad_code
(-ggdb flag enabled)
-rwxr-xr-x  1 chris users 19552  6/28 13:11 bad_code

As you can see, -ggdb adds about 13178 more bytes to the file size over the one with debugging symbols. However, as shown above, this increase in file size can be worth it if presenting debug information to developers. The backtrace can be saved to a file by copying and pasting from the terminal (if it's a non-x based terminal, you can use gpm. To keep this doc simple, I recommend you read up on the documentation for gpm to see how to copy and paste with it). Now that we're done with gdb, we can quit.

(gdb) quit
The program is running. Exit anyway? (y or n) y
$

This ends the walk-through of gdb. Using gdb, we hope that you will be able to use it to create better bug reports. However, there are other types of errors that can cause a program to fail during run time. One of the other ways is through improper file access. We can find those using a nifty little tool called strace.

Finding file access errors using strace

Introduction

Programs often use files to fetch configuration information, access hardware or write logs. Sometimes, a program attempts to reach such files incorrectly. A tool called strace was created to help deal with this. strace traces system calls (hence the name) which include calls that use the memory and files. For our example, we're going to take a program foobar2. This is an updated version of foobar. However, during the change over to foobar2, you notice all your configurations are missing! In foobar version 1, you had it setup to say "foo", but now it's using the default "bar".

$ ./foobar2
Configuration says: bar

Our previous configuration specifically had it set to foo, so let's use strace to find out what's going on.

Using strace to track the issue

We make strace log the results of the system calls. To do this, we run strace with the -o[file] arguments. Let's use it on foobar2 as shown.

# strace -ostrace.log ./foobar2

This creates a file called strace.log in the current directory. We check the file, and shown below are the relevant parts from the file.

open(".foobar2/config", O_RDONLY)       = 3
read(3, "bar", 3)                       = 3

Aha! So There's the problem. Someone moved the configuration directory to .foobar2 instead of .foobar. We also see the program reading in "bar" as it should. In this case, we can recommend the ebuild maintainer to put a warning about it. For now though, we can copy over the config file from .foobar and modify it to produce the correct results.

Conclusion

Now we've taken care of finding run time bugs. These bugs prove to be problematic when you try and run your programs. However, run time errors are the least of your concerns if your program won't compile at all. Let's take a look at how to address emerge compile errors.

Handling emerge Errors

Introduction

emerge errors, such as the one displayed earlier, can be a major cause of frustration for users. Reporting them is considered crucial for maintaining the health of Gentoo. Let's take a look at a sample ebuild, foobar2, which contains some build errors.

Evaluating emerge Errors

Let's take a look at this very simple emerge error:

gcc -D__TEST__ -D__GNU__ -D__LINUX__ -L/usr/lib -I/usr/include -L/usr/lib/nspr/ -I/usr/include/fmod   -c -o foobar2-7.o foobar2-7.c
gcc -D__TEST__ -D__GNU__ -D__LINUX__ -L/usr/lib -I/usr/include -L/usr/lib/nspr/ -I/usr/include/fmod   -c -o foobar2-8.o foobar2-8.c
gcc -D__TEST__ -D__GNU__ -D__LINUX__ -L/usr/lib -I/usr/include -L/usr/lib/nspr/ -I/usr/include/fmod   -c -o foobar2-9.o foobar2-9.c
gcc -D__TEST__ -D__GNU__ -D__LINUX__ -L/usr/lib -I/usr/include -L/usr/lib/nspr/ -I/usr/include/fmod   -c -o foobar2.o foobar2.c
foobar2.c:1:17: ogg.h: No such file or directory
make: *** [foobar2.o] Error 1

!!! ERROR: sys-apps/foobar2-1.0 failed.
!!! Function src_compile, Line 19, Exitcode 2
!!! Make failed!
!!! If you need support, post the topmost build error, NOT this status message

The program is compiling smoothly when it suddenly stops and presents an error message. This particular error can be split into 3 different sections, The compile messages, the build error, and the emerge error message as shown below.

(Compilation Messages)
gcc -D__TEST__ -D__GNU__ -D__LINUX__ -L/usr/lib -I/usr/include -L/usr/lib/nspr/ -I/usr/include/fmod   -c -o foobar2-7.o foobar2-7.c
gcc -D__TEST__ -D__GNU__ -D__LINUX__ -L/usr/lib -I/usr/include -L/usr/lib/nspr/ -I/usr/include/fmod   -c -o foobar2-8.o foobar2-8.c
gcc -D__TEST__ -D__GNU__ -D__LINUX__ -L/usr/lib -I/usr/include -L/usr/lib/nspr/ -I/usr/include/fmod   -c -o foobar2-9.o foobar2-9.c
gcc -D__TEST__ -D__GNU__ -D__LINUX__ -L/usr/lib -I/usr/include -L/usr/lib/nspr/ -I/usr/include/fmod   -c -o foobar2.o foobar2.c

(Build Error)
foobar2.c:1:17: ogg.h: No such file or directory
make: *** [foobar2.o] Error 1

(emerge Error)
!!! ERROR: sys-apps/foobar2-1.0 failed.
!!! Function src_compile, Line 19, Exitcode 2
!!! Make failed!
!!! If you need support, post the topmost build error, NOT this status message

The compilation messages are what lead up to the error. Most often, it's good to at least include 10 lines of compile information so that the developer knows where the compilation was at when the error occurred.

Make errors are the actual error and the information the developer needs. When you see "make: ***", this is often where the error has occurred. Normally, you can copy and paste 10 lines above it and the developer will be able to address the issue. However, this may not always work and we'll take a look at an alternative shortly.

The emerge error is what emerge throws out as an error. Sometimes, this might also contain some important information. Often people make the mistake of posting the emerge error and that's all. This is useless by itself, but with make error and compile information, a developer can get what application and what version of the package is failing. As a side note, make is commonly used as the build process for programs (but not always). If you can't find a "make: ***" error anywhere, then simply copy and paste 20 lines before the emerge error. This should take care of most all build system error messages. Now let's say the errors seem to be quite large. 10 lines won't be enough to catch everything. That's where PORT_LOGDIR comes into play.

emerge and PORT_LOGDIR

PORT_LOGDIR is a portage variable that sets up a log directory for separate emerge logs. Let's take a look and see what that entails. First, run your emerge with PORT_LOGDIR set to your favorite log location. Let's say we have a location /var/log/portage. We'll use that for our log directory:

In the default setup, /var/log/portage does not exist, and you will most likely have to create it. If you do not, portage will fail to write the logs.

# PORT_LOGDIR=/var/log/portage emerge foobar2

Now the emerge fails again. However, this time we have a log we can work with, and attach to the bug later on. Let's take a quick look at our log directory.

# ls -la /var/log/portage
total 16
drwxrws---   2 root root 4096 Jun 30 10:08 .
drwxr-xr-x  15 root root 4096 Jun 30 10:08 ..
-rw-r--r--   1 root root 7390 Jun 30 10:09 2115-foobar2-1.0.log

The log files have the format [counter]-[package name]-[version].log. Counter is a special variable that is meant to state this package as the n-th package you've emerged. This prevents duplicate logs from appearing. A quick look at the log file will show the entire emerge process. This can be attached later on as we'll see in the bug reporting section. Now that we've safely obtained our information needed to report the bug we can continue to do so. However, before we get started on that, we need to make sure no one else has reported the issue. Let's take a look at searching for bugs.

Searching Using Bugzilla

Introduction

Bugzilla is what we at Gentoo use to handle bugs. Gentoo's Bugzilla is reachable by HTTPS and HTTP. HTTPS is available for those on insecure networks or simply paranoid :). For the sake of consistency, we will be using the HTTPS version in the examples to follow. Head over to Gentoo Bugs to see how it looks.

One of the most frustrating things for developers and bug-wranglers is finding duplicate bug reports. These cost them valuable time that they could otherwise use to work on more important bugs. Often, this can be prevented by a few simple search methods. So we're going to see how to search for bugs and find out if you have one that's similar. For this example, we're going to use the xclass emerge error that was used earlier.

/usr/lib/gcc-lib/i686-pc-linux-gnu/3.3.2/include/g++-v3/backward/backward_warning.h:32:2:
warning: #warning This file includes at least one deprecated or antiquated
header. Please consider using one of the 32 headers found in section 17.4.1.2 of
the C++ standard. Examples include substituting the <X> header for the <X.h>
header for C++ includes, or <sstream> instead of the deprecated header
<strstream.h>. To disable this warning use -Wno-deprecated.
In file included from main.cc:40:
menudef.h:55: error: brace-enclosed initializer used to initialize `
OXPopupMenu*'
menudef.h:62: error: brace-enclosed initializer used to initialize `
OXPopupMenu*'
menudef.h:70: error: brace-enclosed initializer used to initialize `
OXPopupMenu*'
menudef.h:78: error: brace-enclosed initializer used to initialize `
OXPopupMenu*'
main.cc: In member function `void OXMain::DoOpen()':
main.cc:323: warning: unused variable `FILE*fp'
main.cc: In member function `void OXMain::DoSave(char*)':
main.cc:337: warning: unused variable `FILE*fp'
make[1]: *** [main.o] Error 1
make[1]: Leaving directory
`/var/tmp/portage/xclass-0.7.4/work/xclass-0.7.4/example-app'
make: *** [shared] Error 2

!!! ERROR: x11-libs/xclass-0.7.4 failed.
!!! Function src_compile, Line 29, Exitcode 2
!!! 'emake shared' failed

So to begin searching, we head over to the Bugzilla Homepage.

We'll click on "Query Existing bug reports". The reason why we choose this over the basic bug search is because the basic bug search tends to give vague results and often hinders users from looking through the results and finding the duplicate bug. Once we click on the query screen, we reach the next page:

If you've used the Advanced Search before, you'll most likely see that screen instead.

Proceed by clicking on the "Advanced Search" link to bring up the Advanced Search page.

This is how the Advanced Search Page looks like. While it may seem overwhelming at first, we're going to look at a few simple areas to narrow down the rather vague searches bugzilla returns.

The first field is the summary of the bug. Here we're simply going to put the name of the package that's crashing. If bugzie doesn't return results, try removing the package name, just in case someone didn't put that in the summary (highly unlikely, but we've seen a fair share of strange bug reports).

Product, Component, and Version should all be set to the default. This prevents us from being too specific and missing all the bugs.

Comment is the important part. Use the comment field to list what appears to be a specific instance of the error. Basically, don't use anything like the beginning of the build error, find a line that's before it stating a true error. Also, you'll want to filter out any punctuation to prevent bugzilla from interpreting the results the comment the wrong way. Example from the xclass emerge error:

menudef.h:78: error: brace-enclosed initializer used to initialize `OXPopupMenu'
(Remove the quotes ' ')
menudef.h 78 error brace-enclosed initializer used to initialize OXPopupMenu

The above is specific enough to where we'll find the bug without wading through other xclass compile failure candidates.

URI, Whiteboard, and Keywords can all be left alone. What we've entered so far should be enough to find our bug. Let's take a look at what we have filled out.

Now we click on the Search button and here come the results...

Only 2 bugs! That's a lot easier to deal with. We click on the first one to check, and sure enough it's the one we're looking for.

Not only is it the one we want, but it has also been resolved. By checking the last comment we see the solution and know what to do in order to resolve it. Now, let's see what would have happened if we had not used the advanced search.

4 more bugs to deal with! It gets even worse with larger packages. However, with these simple tools, we're able to significantly narrow down the search to try and locate a specific bug.

Conclusion

Let's say that you have searched and searched but still can't find a bug. You've found yourself a new bug. Let's take a look at the bug reporting process for submitting your new bug.

Reporting Bugs

Introduction

In this chapter, we'll figure out how to use Bugzilla to file a shiny, new bug. Head over to Gentoo Bugs and...

Click on "Report a Bug - Using the guided format".

As you can see, major emphasis has been placed on putting your bug in the right place. Gentoo Linux is where a large majority of bugs go.

Despite this, some people will file ebuild bugs in portage development (assumption that portage team handles the portage tree) or infra (assumption that infra has access to mirrors and rsync and can fix it directly). This is simply not how things work.

Another common misconception occurs with our Documentation bugs. For example, a user finds a bug with the Catalyst Docs. The general tendency is to file a bug under Docs-user, which gets assigned to the GDP, when it should actually go to a member of the Release Engineering team. As a rule of thumb, only documentation under http://www.gentoo.org/doc/* is under the GDP. Anything under http://www.gentoo.org/proj/* is under the respective teams.

We would rather see a bug whose product was not supposed to be Gentoo Linux but has been filed under the same rather than seeing a bug which belongs the Gentoo Linux product and filed elsewhere. While neither is preferred, the former is more acceptable and understandable (except website bugs.. we might have an issue with that...).

Our bug goes in Gentoo Linux as it's an ebuild bug. We head over there and are presented with the multi-step bug reporting process. Let us now proceed with Step 1...

The first step here is really important (as the red text tells you). This is where you search to see that someone else hasn't hit the same bug you have, yet. If you do skip this step and a bug like yours already exists, it will be marked as a DUPLICATE thus wasting a large amount of QA effort. To give you an idea, the bug numbers that are struck out above are duplicate bugs. Now comes step 2, where we give the information.

Required Information

Let us take a closer look at what's what.

First, there's the Product. The product will narrow down the bug to a specific area of Gentoo like Bugzilla (for bugs relating to bugs.gentoo.org), Docs-user(for User Documentation) or Gentoo Linux (for ebuilds and the like).
Component is where exactly the problem occurs, more specifically which part of selected product the bug comes under. This makes classification easier.
Hardware platform is what architecture you're running. If you were running SPARC, you would set it to SPARC.
Operating System is what Operating System you're using. Because Gentoo is considered a "Meta-distribution", it can run on other operating systems beside Linux.

So, for our example bug, we have :

Product - Gentoo Linux (Since it is an ebuild issue)
Component - Application (It is an application at fault, foobar2)
Hardware Platform - All (This error could occur across architectures)
Operation System - All (It could occur on all types of systems)

Build Identifier is basically the User Agent of the browser that is being used to report the bugs (for logging purposes). You can just leave this as is.
URL is optional and is used to point to errors on a site someplace (pastebin, etc.). However, doing it inside the bug allows the developers be able to reference to it at any time and is preferred.
In the Summary, you should put the package category, name, and number.

Not including the category in the summary really isn't too bad, but it's recommended. If you don't include the package name, however, we won't know what you're filling a bug for, and will have to ask you about it later. The version number is important for people searching for bugs. If 20 people filed bugs and not one put a version number, how would people looking for similar bugs be able to tell if one was there's? They'd have to look through every single bug, which isn't too hard, but if there are say, 200 bugs.. it's not that easy. After all the package information, you'll want to include a small description of the incident. Here's an example:

These simple rules can make handling bugs a lot easier. Next are the details. Here we put in the information about the bug. We'll demonstrate with an example:

Now the developer knows why we're filing the bug. They can then try to reproduce it. Reproducibility tells us how often we were able to make the problem recur. In this example, we can reproduce it any time simply by running foobar2. Let's put that information in.

We have explained how we found the bug. The next step is to explain what were the results we got and what we think they should actually be.

We could then provide additional information. This could be things such as stack traces, sections (since the whole log is usually big and of not much use) of strace logs, but most importantly, your emerge --info output. Here's an example.

Lastly we select the severity of the bug. Please look this over carefully. In most cases it's OK to leave it as is and someone will raise/lower it for you. However, if you raise the severity of the bug, please make sure you read it over carefully and make sure you're not making a mistake. A run down of the various levels is given below.

Blocker - The program just plain doesn't want to emerge or is a major hinderance to the system. For example a baselayout issue which prevents a system from booting up would be a sure candidate to be labelled blocker.
Critical - The program has loss of data or severe memory leaks during runtime. Again, an important program like say net-tools failing to compile could be labelled critical. It won't prevent the system from starting up, but is quite essential for day to day stuff.
Major - The program crashes, but nothing that causes your system severe damage or information loss.
Minor - Your program crashes here and there with apparent workarounds.
Normal - The default. If you're not sure leave it here unless it's a new build or cosmetic change, then read below for more information.
Trivial - Things such as a mispelled word or whitespace clean up.
Enhancement - A request to enable a new feature in a program, or more specifically new ebuilds.

Here, we'll set it to Normal.

Now we can submit the bug report by clicking on the Submit Bug Report box. You will now see your new bug come up. See Bug 97561 for what the result looks like. We've reported our bug! Now let's see how it's dealt with.

Working With Your Bug

Looking at the bug, we see the information we provided earlier. You will notice that the bug has been assigned to bug-wranglers@gentoo.org. This is the default location for Application component bugs.

The details we entered about the bug are available as well.

However, bug-wranglers (usually) won't fix our bugs, so we'll reassign it to someone that can (you can let bug-wranglers re-assign it for you as well). For this we use the package's metadata.xml. You can normally find them in /usr/portage/category/package/metadata.xml. Here's one I've made up for foobar2.

You have to be the reporter of the bug or a member of certain Gentoo Bugzilla groups (like Gentoo Developers) to be able to reassign bugs.

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE pkgmetadata SYSTEM "http://www.gentoo.org/dtd/metadata.dtd">
<pkgmetadata>
<herd>chriswhite</herd>
<maintainer>
<email>chriswhite@gentoo.org</email>
<name>Chris White</name>
</maintainer>
<longdescription lang="en">
Foobar2 is a package that uses a configuration file to display a word.
</longdescription>
</pkgmetadata>

Notice the maintainer section. This lists the maintainer of the package, which in this case is myself, Chris White. The email listed is chriswhite@gentoo.org. We will use this to re-assign the bug to the proper person. To do this, click the bubble next to Reassign bug to, then fill in the email.

A bug for a package without a metadata.xml file should be re-assigned to maintainer-needed@gentoo.org and a package that needs a Gentoo Developer to maintain should be assigned to maintainer-wanted@gentoo.org.

Then hit the Commit button for the changes to take place. The bug has been reassigned to me. Shortly afterward, you notice (by email usually) that I've responded to your bug. I've stated that I'd like to see an strace log to figure out how the program is trying to reach your configuration file. You follow the previous instructions on using strace and obtain an strace log. Now you need to attach it to the bug. In order to do this, click on "Create A New Attachment".

Now we have to attach the log. Let's go throught it step wise.

File - This is the location of the file in your machine. In this example, the location of strace.log. You can use the "Browse..." button to select the file, or enter the path directly in the text field.
Description - A short one liner, or a few wors describing the attachment. We'll just enter strace.log here, since that's quite self-explanatory.
Content Type - This is the type of the file we're attaching to the bug.
Obsoletes - If there were attachements submitted to the bug before the current one, you have an option of declaring them obsoleted by yours. Since we have no prior attachments to this bug, we need not bother.
Comment - Enter comments that will be visible along with the attachments. You could elaborate on the attachment here, if needed.

With respect to Content Type, here are a few more details. You can check the "patch" checkbox if you're submitting a patch. Otherwise, you could ask Bugzilla to "auto-detect" the file type (not advisable). The other options are "select from list", which is most frequently used. Use plain text (text/plain) for most attachments except binary files like images (which can use image/gif, image/jpeg or image/png depending on type) or compressed files like .tar.bz2 which would use application/octet-stream as content type.

We submit strace.log and it is reflected on the bug report.

We've mentioned before that sometimes ebuilds will tell you to attach a file in the emerge error. An example can be seen below.

configure: error: PNG support requires ZLIB. Use --with-zlib-dir=<DIR>

!!! Please attach the config.log to your bug report:
!!! /var/tmp/portage/php-5.0.3-r1/work/php-5.0.3/config.log

!!! ERROR: dev-php/php-5.0.3-r1 failed.
!!! Function econf, Line 485, Exitcode 0
!!! econf failed
!!! If you need support, post the topmost build error, NOT this status message.

Please attach any file mentioned like this to your bug report.

While we're doing all this, suppose another person finds your bug by searching through bugzilla and is curious to keep track of the bug, they may do so by putting their email in the Add CC field of the bug as shown below. You could also keep track of other bugs by following the same method.

Email addresses must be registered with Gentoo Bugzilla. In order to CC multiple addresses, simply separate them with commas or spaces.

After all this work, the bug can undergo various status markings. This is usually done by the Gentoo Developers and sometimes by the reporter. The following are the various possible states a bug may go through during its lifetime.

UNCONFIRMED - You're generally not going to see this too often. This means that a bug reporter has opened a bug using the advanced method and is uncertain his or her bug is an actual bug.
NEW - Bugs that are first opened are considered new.
ASSIGNED - When the person you've assigned the bug too validates your bug, it will often receive ASSIGNED status while they figure out the issue. This lets you know that they've accepted your bug as a real bug.
REOPENED - Someone has resolved a bug and you think the solution is not feasible or the problem still persists. At this point, you may re-open the bug. Please do not abuse this. If a developer closes the bug a second or third time, chances are that your bug is closed.
RESOLVED - A firm decision has been taken on the bug. Usually goes onto FIXED to indicate the bug is solved and the matter closed although various other resolutions are possible. We'll look into those a little later.
VERIFIED - The steps take to work the bug are correct. This is usually a QA thing.
CLOSED - Basically means RIP for the bug and it's buried under the never ending flow of new bugs.

Now shortly afterward, we find the error in the strace log and fix the bug and mark it as RESOLVED FIXED and mention that there was a change in the location of configuration files, and that I will update the ebuild with a warning about it. The bug now becomes resolved, and you are shown the following.

A little below, you'll see the following:

This gives you the option of Reopening the bug if you wish to (i.e. the developer thinks it's resolved but it's really not to your standards). Now our bug is fixed! However, different resolutions can occur. Here's a small list:

FIXED - The bug is fixed, follow the instructions to resolve your issue.
INVALID - You did not do something specifically documented, causing the bug.
DUPLICATE - You didn't use this guide and reported a duplicate bug.
WORKSFORME - Developer/person assigned the bug cannot reproduce your error.
CANTFIX - Somehow the bug cannot be solved because of certain circumstances. These circumstances will be noted by the person taking the bug.
WONTFIX - This is usually applied to new ebuilds or feature requests. Basically the developer does not want to add a certain feature because it is not needed, a better alternative exists, or it's just plain broken. Sometimes you may be given a solution to get said issue resolved.
UPSTREAM - The bug cannot be fixed by the Gentoo development team, and have requested you take the problem upstream (the people that actually made the program) for review. Upstream has a few ways of handling bugs. These include mailing lists, irc channels, and even bug reporting systems. If you're not sure how to contact them, ask in the bug and someone will point you to the right direction.

Sometimes, before the bug can be resolved, a developer may request that you test an updated ebulid. In the next chapter we'll take a look at testing ebuilds.

Testing Ebuilds

Getting The Files

Let's say that you reported a bug for the foobar2 compile fix from earlier. Now developers might find out what the problem is and might need you to test the ebuild for them to be sure it works for you as well:

Some rather confusing vocabulary is used here. First off, let's see what an overlay is. An overlay is a special directory like /usr/portage, the difference being that when you emerge sync, files contained within it will not be deleted. Luckily, a special /usr/local/portage directory is created for that purpose. Let's go ahead and set our portage overlay in/etc/make.conf. Open make.conf up in your favorite editor and add this towards the end.

PORTDIR_OVERLAY="/usr/local/portage"

Now we'll want to create the appropriate directories to put our test ebuild files in. In this case, we're supposed to put them in sys-apps/foobar2. You'll notice that the second comment asks for a files directory for the patch. The files directory holds the digests (md5sums of files for a particular version of a package) and any other required files that aren't included with the standard source archive (patches, init.d scripts, etc). This is a subdir in the package directory called files. Go ahead and create these directories:

# mkdir -p /usr/local/portage/sys-apps/foobar2/files

The -p in mkdir creates not only the directory you want but also any missing parent directories as well (sys-apps and foobar2 in this case).

Ok now, we can go ahead and download the files. First, download the ebuild into /usr/local/portage/sys-apps/foobar2, and then add the patch to /usr/local/portage/sys-apps/foobar2/files. Now that we have the files, we can begin working on testing the ebuild.

Testing The ebuild

The process to create an ebuild that can be used by emerge is fairly simple. You must create a Manifest and a digest file for the ebuild. This can be done with the ebuild command. Run it as shown.

# ebuild foobar2-1.0.ebuild digest
>>> Generating digest file...
<<< foobar2-1.0.tar.bz2
>>> Generating manifest file...
<<< foobar2-1.0.ebuild
<<< files/digest-foobar2-1.0
<<< files/foobar2-1.0-Makefile.patch
>>> Computed message digests.

Now let's test to see if it works as it should.

# emerge -pv foobar2

These are the packages that I would merge, in order:

Calculating dependencies ...done!
[ebuild  N    ] sys-apps/foobar2-1.0  0 kB [1]

Total size of downloads: 0 kB
Portage overlays:
 [1] /usr/local/portage

It does seem to have worked! You'll notice the [1] next to the [ebuild] line. That points to /usr/local/portage, which is the overlay we created earlier. Now we go ahead and emerge the package.

# emerge foobar2
 Calculating dependencies ...done!
(compile info snipped)
>>> Unpacking foobar2-1.0.tar.bz2 to /var/tmp/portage/foobar2-1.0/work
 * Applying foobar2-1.0-Makefile.patch ...                                    [ ok ]
(compile info snipped)
>>> Merging sys-apps/foobar2-1.0 to /
>>> chris +sandbox(preinst)
--- /usr/
--- /usr/bin/
>>> /usr/bin/foobar2

In the first section we see that the emerge started off as it should. The second section shows our patch being applied successfully by the "[ ok ]" status message to the right. The last section tells us the program compiled ok. The patch works! Now we can go and let the developer know that their patch works fine, and that they can commit the fix to portage.

Conclusion

This concludes the howto on working with Bugzilla. I hope you find this useful. If you have any questions, comments, or ideas regarding this document, please send them to me at chriswhite@gentoo.org. Special thanks go to moreon for his notes on -g flags and compile errors, the people at #gentoo-bugs for helping out with bug-wrangling, Griffon26 for his notes on maintainer-needed, robbat2 for general suggestions and fox2mike for fixing up the doc and adding stuff as needed.