What You Think Should Happen Instead

Oct 13, 2025 by wbrum.org 5 views

Bug Report: appendonlyam_handler.c:1790:25: error: ‘segfile_count’ may be used uninitialized

Apache Cloudberry is an open-source, distributed, and scalable data storage system designed to handle large amounts of data efficiently. However, like any complex software, it is not immune to bugs and errors. In this article, we will report a bug in the appendonlyam_handler.c file, which is causing an error due to the possible uninitialized use of the 'segfile_count' variable.

Apache Cloudberry Version

The main branch commit used for this bug report is 644b4e307380954e986f048d0a7910a3063e524e.

Error Description

The error occurs in the appendonlyam_handler.c file, specifically in the 'appendonly_index_build_range_scan' function. The error message is as follows:

appendonlyam_handler.c: In function ‘appendonly_index_build_range_scan’:
appendonlyam_handler.c:1790:25: error: ‘segfile_count’ may be used uninitialized [-Werror=maybe-uninitialized]
 1790 |                         FreeAllSegFileInfo(seginfo, segfile_count);
      |                         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
aocsam_handler.c: In function ‘aoco_index_build_range_scan’:
aocsam_handler.c:1952:25: error: ‘segfile_count’ may be used uninitialized [-Werror=maybe-uninitialized]
 1952 |                         FreeAllAOCSSegFileInfo(seginfo, segfile_count);
      |                         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
cc1: all warnings being treated as errors

What Happened

The error occurs when the 'segfile_count' variable is used without being initialized. This can lead to unexpected behavior and crashes.

What You Think Should Happen Instead

In this case, the expected behavior is that the 'segfile_count' variable should be initialized before being used. This can be achieved by adding a check to ensure that the variable is initialized before using it.

How to Reproduce

To reproduce this bug, follow these steps:

Clone the Apache Cloudberry repository using the following command:

git clone https://github.com/apache/cloudberry.git

Navigate to the cloned repository and switch to the main branch using the following command:

git checkout main

Apply the commit 644b4e307380954e986f048d0a7910a3063e524e using the following command:

git apply 644b4e307380954e986f048d0a7910a3063e524e

Run the following command to build the project:

make

The error should occur during the build process.

Operating System

The bug was reproduced on an Ubuntu operating system.

Anything Else

No additional information is available.

Are You Willing to Submit PR?

Yes, I am willing to submit a PR to fix this bug.

Code of Conduct

I agree to follow this project's Code of Conduct.

In conclusion, the bug in the appendonlyam_handler.c file is causing an error due to the possible uninitialized use of the 'segfile_count' variable. To fix this bug, we need to initialize the 'segfile_count' variable before using it. We will submit a PR to fix this bug and ensure that the project is stable and efficient.

To fix this bug, we need to add a check to ensure that the 'segfile_count' variable is initialized before using it. We can do this by adding a conditional statement to check if the variable is initialized before using it.

Here is the corrected code:

if (segfile_count > 0) {
    FreeAllSegFileInfo(seginfo, segfile_count);
} else {
    // Handle the case where segfile_count is not initialized
}

We will submit a PR to fix this bug and ensure that the project is stable and efficient.

Here is the commit message for the PR:

Fix bug in appendonlyam_handler.c:1790:25: error: ‘segfile_count’ may be used uninitialized

Add a check to ensure that the ‘segfile_count’ variable is initialized before using it.
```<br/>
**Q&A: Bug Report - appendonlyam_handler.c:1790:25: error: ‘segfile_count’ may be used uninitialized**

**Introduction**
===============

In our previous article, we reported a bug in the appendonlyam_handler.c file, which is causing an error due to the possible uninitialized use of the 'segfile_count' variable. In this article, we will provide a Q&A section to address any questions or concerns related to this bug report.

**Q: What is the cause of the bug?**
-----------------------------------

A: The bug is caused by the possible uninitialized use of the 'segfile_count' variable. This variable is used to store the count of segment files, but it is not initialized before being used.

**Q: How can I reproduce the bug?**
-----------------------------------

A: To reproduce the bug, follow these steps:

1. Clone the Apache Cloudberry repository using the following command:
```bash
git clone https://github.com/apache/cloudberry.git

Navigate to the cloned repository and switch to the main branch using the following command:

git checkout main

Apply the commit 644b4e307380954e986f048d0a7910a3063e524e using the following command:

git apply 644b4e307380954e986f048d0a7910a3063e524e

Run the following command to build the project:

make

The error should occur during the build process.

Q: What is the expected behavior?

A: The expected behavior is that the 'segfile_count' variable should be initialized before being used. This can be achieved by adding a check to ensure that the variable is initialized before using it.

Q: How can I fix the bug?

A: To fix the bug, you can add a check to ensure that the 'segfile_count' variable is initialized before using it. Here is an example of the corrected code:

if (segfile_count > 0) {
    FreeAllSegFileInfo(seginfo, segfile_count);
} else {
    // Handle the case where segfile_count is not initialized
}

Q: What is the impact of this bug?

A: The impact of this bug is that it can cause unexpected behavior and crashes when the 'segfile_count' variable is used without being initialized.

Q: How can I prevent this bug in the future?

A: To prevent this bug in the future, you can follow these best practices:

Always initialize variables before using them.
Use checks to ensure that variables are initialized before using them.
Use debuggers and testing tools to catch bugs early.

Q: Can I submit a PR to fix this bug?

A: Yes, you can submit a PR to fix this bug. We appreciate any contributions to the Apache Cloudberry project.

Q: What is the next step?

A: The next step is to submit a PR to fix this bug and ensure that the project is stable and efficient.

In conclusion, the bug in the appendonlyam_handler.c file is causing an error due to the possible uninitialized use of the 'segfile_count' variable. We have provided a Q&A section to address any questions or concerns related to this bug report. We encourage anyone who is interested in contributing to the Apache Cloudberry project to submit a PR to fix this bug.