Go to Definition jumps to .h declaration instead of .c definition in 1.33.2 (regression from 1.32.2)

[hhhwcyjhh]

Environment

• OS: Windows 10 Pro for Workstations
• VS Code version: (your version)
• C/C++ extension version: 1.33.2 (broken), 1.32.2 (works)
• Project type: Embedded C firmware (esirisc architecture)
• Workspace on: mapped virtual drive (M:)

Problem

After upgrading to 1.33.2, pressing F12 (Go to Definition) on a function
always jumps to the declaration in the .h header file instead of the
implementation in the .c source file. Downgrading to 1.32.2 restores
correct behavior immediately.

Steps to Reproduce

1. Open a C project on a mapped virtual drive
2. Open a source file (e.g. FlowWork.c)
3. Press F12 on a function call (e.g. AppFrontFilter())
4. Expected: jumps to AppFrontFilter.c:929 (definition)
5. Actual: jumps to AppFrontFilter.h:77 (declaration)

Additional Info

• The issue occurs even when the target .c file is open in the editor
• compile_commands.json is configured and loaded correctly (verified via Log Diagnostics)
• The browse database is fully built (verified via C/C++ Output channel)
• Downgrading to 1.32.2 fixes the issue without any other changes

[sean-mcmanus]

hhhwcyjhh Why are you using 1.33.2 instead of 1.33.7? Do you still repro it with 1.33.7 too?

[sean-mcmanus]

hhhwcyjhh I don't repro the bug. There may be some problem parsing the AppFrontFilter.c file. We fixed some issues from 1.33.3 to 1.33.7 which could cause this. Are you able to try 1.33.7 (or the pending 1.33.8) and try to get an isolated/minimum repro or sample code?

[11cookies11]

I encountered a similar issue after updating the Microsoft C/C++ extension
to version 1.33.8.

After the update, IntelliSense indexing and symbol lookup stopped working
in my IAR-based embedded project.

Environment:

• OS: Windows 11
• VS Code: [1.133.0]
• Microsoft C/C++ extension: 1.33.8
• Compiler: IAR Embedded Workbench / ICCARM
• Project type: FreeRTOS + EtherCAT + lwIP embedded project
• Project size: approximately 705 C/C++ source files

Problem:
After upgrading the Microsoft C/C++ extension to version 1.33.8,
IntelliSense indexing and symbol lookup became unreliable.

Observed behavior:

• "Go to Definition" frequently returns no result.
• Symbol search does not find existing functions or variables.
• The browse database reports access or query errors.
• The index is not fully populated.
• Parsing may stop after processing only a small number of files.
• Resetting or rebuilding the browse database does not reliably fix the issue.
• The project can still be opened and built successfully in IAR.

The project contains:

• IAR compiler configuration
• FreeRTOS
• lwIP
• EtherCAT SSC sources
• Generated headers
• A large number of include directories
• Multiple application and bootloader source trees

Workaround:
I rolled back the Microsoft C/C++ extension from version 1.33.8
to version 1.32.2.

After the rollback, the issue disappeared. The C/C++ output log reported:

• cpptools TypeScript version: 1.32.2
• cpptools native version: 1.32.2.0
• Approximately 705 files processed
• browseErrors=0
• Symbol lookup and indexing work normally

Expected behavior:
The Microsoft C/C++ extension should reliably parse and index large
IAR-based embedded projects, including projects with generated headers,
custom compiler configurations, and multiple include directories.

Could you please investigate whether the browse database or the parsing
changes introduced in version 1.33.8 caused this regression?

I can provide sanitized logs and configuration files if needed.
For confidentiality reasons, I cannot provide the original source code
or protected project files.

[hhhwcyjhh]

hhhwcyjhh Why are you using 1.33.2 instead of 1.33.7? Do you still repro it with 1.33.7 too?

I have the same problem when using version 1.33.8.