Qt项目重建遇LNK1181错误：无法打开release\main.obj求助

Hey there, let's break down your problem and fix it step by step!

First off, the core issue here is version mismatch between Qt and MSVC. Qt's pre-built binaries are tightly coupled with specific MSVC toolchains: Qt 5.8.0 was officially compiled for MSVC2013, and it doesn't support MSVC2017 (Qt started full MSVC2017 support from version 5.9 onwards). When you try to build the project with MSVC2017, the linker can't find release\main.obj because the compiler generates incompatible object files, and the misconfigured kit amplifies this issue.

1. Fix the Qt-MSVC Version Match #

You have two solid options here:

• Option 1: Install MSVC2013 Toolchain
  You don't need a full Visual Studio 2013 installation. Just open the Visual Studio Installer, add the "Visual C++ 2013 Toolset" component to your existing VS2017 setup. Then go back to Qt Creator and configure the Desktop Qt 5.8.0 MSVC2013 64bit kit with this toolchain.
• Option 2: Upgrade Qt to a MSVC2017-Compatible Version
  Switch to a Qt version that supports MSVC2017, like the LTS release Qt 5.12.x (it's more stable and has longer support). Download the pre-built Qt 5.12.x MSVC2017 64bit package from Qt's official archive, then set up a new kit in Qt Creator for this version.

2. Resolve Kit Configuration Issues #

No matter which option you choose, make sure your Qt Creator kit is properly set up:

• Open Qt Creator, go to Tools > Options > Build & Run > Kits
• Select the kit you want to use:
  • Under Compiler, pick the matching MSVC toolchain (e.g., MSVC2013 x64 or MSVC2017 x64)
  • Under Qt Version, select the Qt binary that matches the compiler (e.g., Qt 5.8.0 MSVC2013 64bit or Qt 5.12.12 MSVC2017 64bit)
  • Ensure the Debugger is correctly linked (Qt Creator usually detects the Windows CDB automatically; if not, install it via the Windows SDK)
• If the kit shows a configuration error, click the Repair button, or manually browse to the correct compiler/Qt installation paths.

3. Clean and Rebuild from Scratch #

Old build artifacts are often the culprit for weird linker errors:

• Delete the entire build- folder of your project (this holds all the old compiled files in release/debug subfolders)
• In Qt Creator, click Build > Clean Project [YourProjectName]
• Run qmake first: Build > Run qmake
• Finally, click Build > Build Project [YourProjectName]

4. Verify .pro File Compatibility #

If you upgraded Qt, double-check your .pro file for Qt 5.8-specific code:

• Ensure module references are standard, e.g., QT += core gui widgets
• Remove any custom compiler flags (QMAKE_CXXFLAGS) that might not work with MSVC2017
• If your project uses deprecated Qt 5.8 APIs, replace them with their Qt 5.12 equivalents (check Qt's documentation for migration tips)

• Always prioritize version compatibility: Check Qt's official support matrix before pairing Qt with an MSVC version (Qt 5.8 supports MSVC2010/2013; Qt 5.9+ supports MSVC2015/2017)
• Use separate build directories: In Projects > Build & Run > Build Directory, set unique paths for different kits (e.g., 32bit/64bit, different compilers) to avoid file conflicts
• Keep shadow build enabled: Qt Creator's default shadow build keeps compiled files separate from your source code—never disable this, it makes cleaning and switching configurations way easier
• Clear build cache regularly: If you hit odd compile errors, first delete the build directory and rebuild. Stale cache files cause more issues than you'd think!
• Name kits clearly: Give your kits descriptive names like "Qt 5.12.12 MSVC2017 x64 Debug" so you can quickly switch between configurations without confusion

内容的提问来源于stack exchange，提问作者Abu Muhammad