I apologize if this is trivial, but I'm not a regular VS user and my Google-Fu is turning up nothing obvious or simple.
I have inherited responsibility for a large (500k+ LOC, a dozen solutions, hundreds of projects) repository that's been forked a number of times in the past. The solution/project structure is... spaghetti-esque, in that the filesystem folder structure and the solution/project structure are only weakly correlated, and many projects import/reference other projects outside the filesystem folder hierarchy of their containing solution, and that are not even part of the containing solution.
For example:
c:\SolutionA\SolutionA.sln contains c:\SolutionA\ProjectB.csproj and c:\SolutionA\ProjectC.csproj. But C:\solution\ProjectC.csproj contains a <Import Project="..\SomeOtherRandomSolutionDir\ProjectD.csproj" /> reference.
I know there are a lot of projects/files/resources in this repo that are not used by any of the solutions I'm actually building and I don't need them, but the tentacular nature of the project imports/references makes it hard to determine what's actually necessary for the builds and what's superfluous.
So: is there any relatively simple way to run a solution build in Visual Studio (or MSBuild) and obtain a list of every single file used by the build process? I've tried creating a diagnostic-level build log and grepping[1] it for the repo base path; will that get me what I want? (Narrator: it won't)
EDIT: Assume that all file operations are done entirely by default Visual Studio solution project handling and there's no custom targets or shelling out to copy or move files, in the way Perry Qian describes below
[1] Well, Get-Content | Select-String-ing it, but that's clunkier to say
is there any relatively simple way to run a solution build in Visual
Studio (or MSBuild) and obtain a list of every single file used by the
build process? I've tried creating a diagnostic-level build log and
grepping[1] it for the repo base path; will that get me what I want?
Sorry but I'm afraid this is not supported scenario. You cannot obtain a list of every single files that are used in a project or a solution during build process.
Let me explain it more detailed:
Usually the files which are in the solution explorer are all useful in the project. Since your solution is too large and logically complex, we do not recommend deleting any of the files, and I think they all work.
We can obtain a list of files which are parts of the input items of the projects by MSBuild(usually in <Itemgroup> node of the xxx.csproj file).This is the only way I can think of to get a set of project files through MSBuild. We can add this target into xxx.csproj to list all of them like this:
<Target Name="ShowSingleProjectItemList" AfterTargets="Build">
<Message Importance="high" Text="None file:#(None)---Compile files:#(Compile)---Content files:#(Content)---Embedded Resource files:#(EmbeddedResource)---CodeAnalysisDictionary files:#(CodeAnalysisDictionary)---ApplicationDefinition files:#(ApplicationDefinition)---Page files:#(Page)---Resource files:#(Resource)---SplashScreen files:#(SplashScreen)---DesignData files: #(DesignData) Reference dlls :#(Reference)">
</Target>
Note that this method can only be used for each project and not for the entire solution so if you want to use, add it into every xxx.csproj file.
But for other files which are not as the input items of the projects and added or referenced in the projects by some CMD commands or powershell scripts, build events(Right-click on Project-->Properties-->Build Events)(You can refer to this) and any other custom target in the xxx.csproj,we cannot list all of them by a function.
For example, if you use powershell to do some copy operation like coping some dlls from the path outside of your solution into projects,they can't stay in the project as an item of the project. So we cannot obtain them by MSBuild.
For this situation, we can only manually view all of them that are imported into the projects in whatever way in the diagnostic-level build log.
Conclusion
As input items of the projects, we can get the required files for each project by MSBuild, but for some other operations(powershell,build events,etc) to add files from other path outside into the current project,we cannot retrieve all of their information by a method. You can only look it up one by one by diagnostible-level build log.
Besides,we don't know the structure and logic of the entire solution, so we can't guarantee that every file is an item element, so for now you have to look at it manually.
Update 1
To avoid adding every target into your xxx.csproj(since you have a lot of projects under a solution), you can try to use Directory.Build.props. You just write the custom target into this file and then put the file under your solution. After that, when you build the solution, the build will execute into every project so that you just have to write it once.
Solution
1) create a file namedDirectory.Build.props under the solution
2) write these info into the file
<Target Name="ShowSingleProjectItemList" AfterTargets="Build">
<Message Importance="high" Text="None file:#(None)---Compile files:#(Compile)---Content files:#(Content)---Embedded Resource files:#(EmbeddedResource)---CodeAnalysisDictionary files:#(CodeAnalysisDictionary)---ApplicationDefinition files:#(ApplicationDefinition)---Page files:#(Page)---Resource files:#(Resource)---SplashScreen files:#(SplashScreen)---DesignData files: #(DesignData) Reference dlls :#(Reference)">
</Target>
3) build your solution and you will find the files in the build output window.
I'm trying to write a code generation tool. For this tool it's important that the generated code is available prior to building (i.e., for IntelliSense). I know Visual Studio will at least partially evaluate the project build plan automatically to generate IntelliSense, but I can't find much information on the details.
As a simpler example, let's say I want to take all items with build action None and compile them. I have a project like this:
<Project [...]>
[...]
<Compile Include="Foo.cs" />
<None Include="Bar.cs" />
</Project>
One way to get Bar.cs to compile is to add the following to the project:
<PropertyGroup>
<CoreCompileDependsOn>
$(CoreCompileDependsOn);IndirectCompile
</CoreCompileDependsOn>
</PropertyGroup>
<Target Name="IndirectCompile">
<CreateItem Include="#(None)">
<Output ItemName="Compile" TaskParameter="Include" />
</CreateItem>
</Target>
If I do it this way, Visual Studio acts basically the same as if Bar.cs had the Compile action to begin with. IntelliSense is fully available; if I make a change in Bar.cs it's reflected immediately (well, as immediate as the background operation normally is) in IntelliSense when I'm editing Foo.cs, and so on.
However, say instead of directly compiling the None entry, I want to copy it to the obj directory and then compile it from there. I can do this by changing the IndirectCompile target to this:
<Target Name="IndirectCompile"
Inputs="#(None)"
Outputs="#(None->'$(IntermediateOutputPath)%(FileName).g.cs')"
>
<Copy SourceFiles="#(None)"
DestinationFiles="#(None->'$(IntermediateOutputPath)%(FileName).g.cs')"
>
<Output TaskParameter="DestinationFiles" ItemName="Compile" />
</Copy>
</Target>
Doing this causes IntelliSense to stop updating. The task works on build, dependency analysis and incremental building work, Visual Studio just stops automatically running it when an input file is saved.
So, that leads to the title question: How does Visual Studio choose to run targets or not for IntelliSense? The only official documentation I've found has been this, specifically the "Design-Time IntelliSense" section. I'm pretty sure my code meets all those criteria. What am I missing?
After a few days of experimenting and poking around in the debugger I think I have found the answer, and unfortunately that answer is that this is not possible (at least not in a clearly supported way -- I'm sure there are ways to trick the system).
When a project is loaded, and when the project itself changes (files added/removed, build actions changed, etc), the IntelliSense build is executed (csproj.dll!CLangCompiler::RunIntellisenseBuild). This build will run tasks up to and including the Csc task. Csc will not execute normally, but instead just feed its inputs back into its host (Visual Studio).
From this point on, Visual Studio keeps track of the files that were given as Sources to the Csc task. It will monitor those files for changes, and when they change, update IntelliSense. So in my example, if I manually edit Bar.g.cs those changes will be picked up. But the build tasks themselves will not be run again until the project changes or a build is explicitly requested.
So, that's disappointing, but not surprising, I guess. It also explains something else I had always wondered about -- XAML files with a code-behind tend to have a Custom Tool action of MSBuild:Compile, presumably for exactly this reason.
I'm going to mark this as the answer, but I'd love to be told I'm wrong and that I missed something.
Our code uses different settings for development and production environments so we were looking at using VS2010's web.config transform capabilities. After hours of trial and error, nothing has worked. We found a Web.config transformation tester and found that what we had been trying was supposed to work (according to this tool.)
We tried testing the transformations using Build, not Publish. Does it only run on Publish or could something else be wrong?
Yes, it only runs on Publish. To test, publish to a local dir. You'll want to publish your application with the correct target environment set.
You can also integrates web config transformations with MS Build.
It seems you don't have to be in Publish mode to generate a transformed Web.config file. There's just a bit more work involved.
Open the Visual Studio Command Prompt and navigate to your working project directory that contains your .csproj file. Enter the following command:
MSBuild project.csproj /t:TransformWebConfig /p:Configuration=Debug
The example above would run the Debug transformation during the build of project.csproj. This will output a Web.config file into the obj\Debug\TransformWebConfig\transformed\ directory, where Debug is whatever Configuration you set in the command above.
Copy this file to replace your root Web.config file, and you're done. You could write a batch script to run both of those items automatically, but for larger projects with many configurations it could become unwieldy.
You might be able to add those command line arguments to the build process inside of Visual Studio, but I'm not sure how - as far as I know for this method to work you would have to build from the command line instead of inside Visual Studio. You can still use Clean inside of Visual Studio to clean out the obj folder but it will only clean the solution configuration mode selected in the IDE. Clean will not revert your edited web.config file, so you may want to back it up before proceeding if you need to.
(Command line arguments found from this MSDN article.)
You don't need run Publish/Build Package in order to test Web.config transformation. There is a cool trick to quickly know the transformation result here. Scroll down until you see a comment about creating TransformConfig project. It works like a charm, note that you can safely ignore 7th step (frankly I don't know how to do that step properly but fortunately we don't need it :)).
I would like to have MSTest (honestly, I'd take whatever at this point) run my tests post-build, and then if any tests fail, produce the standard file(lineno): message output that Visual Studio recognizes and allows me to go straight to the failure point.
Or, if possible, then after a successful build I'd like the "Run All Tests in Solution" Visual Studio command to fire automatically.
As far as I can tell, this isn't possible. The commandline version of MSTest does not produce correctly formatted output (and as far as I can tell, neither does NUnit or xUnit), so when I add MSTest to my project's Post Build, I still have to scroll around, looking for the one that failed. The in-IDE version works ok, as long as I remember to hit Ctrl-R,A when the build finishes.
You can get what you are looking for by making a custom target in your project file instead of using the pre-baked PostBuild target. Add something like this right into your project file, editing it as XML,
<Target Name="RunUnitTests"
AfterTargets="CoreBuild">
<Exec
Command="mstest /testcontainer:$(OutDir)\PathToUnitTests\UnitTests.dll"
CustomErrorRegularExpression="^Failed"
/>
</Target>
You'll need to properly set the path to your test assembly or whatever other method you are using (test config file etc.), and you may need to tweak the regex, going from memory here...
This will run mstest similar to how you are probably doing in the PostBuild, but adds in the ability for MSBuild (which is what drives the C# build system) to detect output strings that it should consider errors. There is a similar parameter for a CustomWarningRegularExpression also.
If you want to share this among multiple projects, look up "MSBuild Imports"
I've switched to xUnit, and with a minor change to their MSBuild unit test runner, I get what I want.
I have a very similar problem as described here.
I also upgraded a mixed solution of C++/CLI and C# projects from Visual Studio 2008 to Visual Studio 2010. And now in Visual Studio 2010 one C++/CLI project always runs out of date.
Even if it has been compiled and linked just before and F5 is hit, the messagebox "The project is out of date. Would you like to build it?" appears. This is very annoying because the DLL file is very low-tiered and forces almost all projects of the solution to rebuild.
My pdb settings are set to the default value (suggested solution of this problem).
Is it possible the get the reason why Visual Studio 2010 forces a rebuild or thinks a project is up to date?
Any other ideas why Visual Studio 2010 behaves like that?
For Visual Studio/Express 2010 only. See other (easier) answers for VS2012, VS2013, etc
To find the missing file(s), use info from the article Enable C++ project system logging to enable debug logging in Visual Studio and let it just tell you what's causing the rebuild:
Open the devenv.exe.config file (found in %ProgramFiles%\Microsoft Visual Studio 10.0\Common7\IDE\ or in %ProgramFiles(x86)%\Microsoft Visual Studio 10.0\Common7\IDE\). For Express versions the config file is named V*Express.exe.config.
Add the following after the </configSections> line:
<system.diagnostics>
<switches>
<add name="CPS" value="4" />
</switches>
</system.diagnostics>
Restart Visual Studio
Open up DbgView and make sure it's capturing debug output
Try to debug (hit F5 in Visual Studio)
Search the debug log for any lines of the form:
devenv.exe Information: 0 : Project 'Bla\Bla\Dummy.vcxproj' not up to date because build input 'Bla\Bla\SomeFile.h' is missing.
(I just hit Ctrl+F and searched for not up to date) These will be the references causing the project to be perpetually "out of date".
To correct this, either remove any references to the missing files from your project, or update the references to indicate their actual locations.
Note: If using 2012 or later then the snippet should be:
<system.diagnostics>
<switches>
<add name="CPS" value="Verbose" />
</switches>
</system.diagnostics>
In Visual Studio 2012 I was able to achieve the same result easier than in the accepted solution.
I changed the option in menu Tools → Options → Projects and Solutions → Build and Run → *MSBuild project build output verbosity" from Minimal to Diagnostic.
Then in the build output I found the same lines by searching for "not up to date":
Project 'blabla' is not up to date. Project item 'c:\foo\bar.xml' has 'Copy to Output Directory' attribute set to 'Copy always'.
This happened to me today. I was able to track down the cause: The project included a header file which no longer existed on disk.
Removing the file from the project solved the problem.
We also ran into this issue and found out how to resolve it.
The issue was as stated above "The file no longer exists on the disk."
This is not quite correct. The file does exist on the disk, but the .VCPROJ file is referencing the file somewhere else.
You can 'discover' this by going to the "include file view" and clicking on each include file in turn until you find the one that Visual Studio can not find. You then ADD that file (as an existing item) and delete the reference that can not be found and everything is OK.
A valid question is: How can Visual Studio even build if it does not know where the include files are?
We think the .vcproj file has some relative path to the offending file somewhere that it does not show in the Visual Studio GUI, and this accounts for why the project will actually build even though the tree-view of the includes is incorrect.
The accepted answer helped me on the right path to figuring out how to solve this problem for the screwed up project I had to start working with. However, I had to deal with a very large number of bad include headers. With the verbose debug output, removing one caused the IDE to freeze for 30 seconds while outputting debug spew, which made the process go very slowly.
I got impatient and wrote a quick-and-dirty Python script to check the (Visual Studio 2010) project files for me and output all the missing files at once, along with the filters they're located in. You can find it as a Gist here: https://gist.github.com/antiuniverse/3825678 (or this fork that supports relative paths)
Example:
D:\...> check_inc.py sdk/src/game/client/swarm_sdk_client.vcxproj
[Header Files]:
fx_cs_blood.h (cstrike\fx_cs_blood.h)
hud_radar.h (cstrike\hud_radar.h)
[Game Shared Header Files]:
basecsgrenade_projectile.h (..\shared\cstrike\basecsgrenade_projectile.h)
fx_cs_shared.h (..\shared\cstrike\fx_cs_shared.h)
weapon_flashbang.h (..\shared\cstrike\weapon_flashbang.h)
weapon_hegrenade.h (..\shared\cstrike\weapon_hegrenade.h)
weapon_ifmsteadycam.h (..\shared\weapon_ifmsteadycam.h)
[Source Files\Swarm\GameUI - Embedded\Base GameUI\Headers]:
basepaenl.h (swarm\gameui\basepaenl.h)
...
Source code:
#!/c/Python32/python.exe
import sys
import os
import os.path
import xml.etree.ElementTree as ET
ns = '{http://schemas.microsoft.com/developer/msbuild/2003}'
#Works with relative path also
projectFileName = sys.argv[1]
if not os.path.isabs(projectFileName):
projectFileName = os.path.join(os.getcwd(), projectFileName)
filterTree = ET.parse(projectFileName+".filters")
filterRoot = filterTree.getroot()
filterDict = dict()
missingDict = dict()
for inc in filterRoot.iter(ns+'ClInclude'):
incFileRel = inc.get('Include')
incFilter = inc.find(ns+'Filter')
if incFileRel != None and incFilter != None:
filterDict[incFileRel] = incFilter.text
if incFilter.text not in missingDict:
missingDict[incFilter.text] = []
projTree = ET.parse(projectFileName)
projRoot = projTree.getroot()
for inc in projRoot.iter(ns+'ClInclude'):
incFileRel = inc.get('Include')
if incFileRel != None:
incFile = os.path.abspath(os.path.join(os.path.dirname(projectFileName), incFileRel))
if not os.path.exists(incFile):
missingDict[filterDict[incFileRel]].append(incFileRel)
for (missingGroup, missingList) in missingDict.items():
if len(missingList) > 0:
print("["+missingGroup+"]:")
for missing in missingList:
print(" " + os.path.basename(missing) + " (" + missing + ")")
I've deleted a cpp and some header files from the solution (and from the disk) but still had the problem.
Thing is, every file the compiler uses goes in a *.tlog file in your temp directory.
When you remove a file, this *.tlog file is not updated. That's the file used by incremental builds to check if your project is up to date.
Either edit this .tlog file manually or clean your project and rebuild.
I had a similar problem, but in my case there were no files missing, there was an error in how the pdb output file was defined: I forgot the suffix .pdb (I found out with the debug logging trick).
To solve the problem I changed, in the vxproj file, the following line:
<ProgramDataBaseFileName>MyName</ProgramDataBaseFileName>
to
<ProgramDataBaseFileName>MyName.pdb</ProgramDataBaseFileName>
I had this problem in VS2013 (Update 5) and there can be two reasons for that, both of which you can find by enabling "Detailed" build output under "Tools"->"Projects and Solutions"->"Build and Run".
"Forcing recompile of all source files due to missing PDB "..."
This happens when you disable debug information output in your compiler options (Under Project settings: „C/C++“->“Debug Information Format“ to „None“ and „Linker“->“Generate Debug Info“ to „No“: ). If you have left „C/C++“->“Program Database File Name“ at the default (which is „$(IntDir)vc$(PlatformToolsetVersion).pdb“), VS will not find the file due to a bug (https://connect.microsoft.com/VisualStudio/feedback/details/833494/project-with-debug-information-disabled-always-rebuilds).
To fix it, simply clear the file name to "" (empty field).
"Forcing rebuild of all source files due to a change in the command line since the last build."
This seems to be a known VS bug too (https://connect.microsoft.com/VisualStudio/feedback/details/833943/forcing-rebuild-of-all-source-files-due-to-a-change-in-the-command-line-since-the-last-build) and seems to be fixed in newer versions (but not VS2013). I known of no workaround, but if you do, by all means, post it here.
I don't know if anyone else has this same problem, but my project's properties had "Configuration Properties" -> C/C++ -> "Debug Information Format" set to "None", and when I switched it back to the default "Program Database (/Zi)", that stopped the project from recompiling every time.
Another simple solution referenced by Visual Studio Forum.
Changing configuration: menu Tools → Options → Projects and Solutions → VC++ Project Settings → Solution Explorer Mode to Show all files.
Then you can see all files in Solution Explorer.
Find the files marked by the yellow icon and remove them from the project.
It's OK.
Visual Studio 2013 -- "Forcing recompile of all source files due to missing PDB". I turned on detailed build output to locate the issue: I enabled "Detailed" build output under "Tools" → "Projects and Solutions" → "Build and Run".
I had several projects, all C++, I set the option for under project settings: (C/C++ → Debug Information Format) to Program Database (/Zi) for the problem project. However, this did not stop the problem for that project. The problem came from one of the other C++ projects in the solution.
I set all C++ projects to "Program Database (/Zi)". This fixed the problem.
Again, the project reporting the problem was not the problem project. Try setting all projects to "Program Database (/Zi)" to fix the problem.
I met this problem today, however it was a bit different. I had a CUDA DLL project in my solution. Compiling in a clean solution was OK, but otherwise it failed and the compiler always treated the CUDA DLL project as not up to date.
I tried the solution from this post.
But there is no missing header file in my solution. Then I found out the reason in my case.
I have changed the project's Intermediate Directory before, although it didn't cause trouble. And now when I changed the CUDA DLL Project's Intermediate Directory back to $(Configuration)\, everything works right again.
I guess there is some minor problem between CUDA Build Customization and non-default Intermediate Directory.
I had similar problem and followed the above instructions (the accepted answer) to locate the missing files, but not without scratching my head. Here is my summary of what I did. To be accurate these are not missing files since they are not required by the project to build (at least in my case), but they are references to files that don't exist on disk which are not really required.
Here is my story:
Under Windows 7 the file is located at %ProgramFiles(x86)%\Microsoft Visual Studio 10.0\Common7\IDE\%. There are two similar files devenv.exe.config.config and devenv.exe.config. You want to change later one.
Under Windows 7, you don't have permission to edit this file being in program files. Just copy it somewhere else (desktop) change it and than copy it back to the program files location.
I was trying to figure out how to connect DebugView to the IDE to see the missing files. Well, you don't have to do anything. Just run it, and it will capture all the messages. Make sure Capture Events menu option is selected in Capture menu which by default should be selected.
DebugView will NOT display all the missing files at once (at least it didn't for me)! You would have DebugView running and than run the project in Visual Studio 2010. It will prompt the project out of date message, select Yes to build and DebugView will show the first file that is missing or causing the rebuild. Open the project file (not solution file) in Notepad and search for that file and delete it. You are better off closing your project and reopening it again while doing this delete. Repeat this process until DebugView no longer shows any files missing.
It's kind of helpful to set the message filter to not up to date from the DebugView toolbar button or Edit → Filter/Highlight option. That way the only messages it displays are the one that has `not up to date' string in it.
I had lots of files that were unnecessary references and removing them all fixed the issue following the above steps.
Second way to find all the missing files at once
There is a second way to find these files all at once, but it involves (a) source control and (b) integration of it with Visual Studio 2010. Using Visual Studio 2010, add your project to a desired location or dummy location in source control. It will try to add all the files, including those that don't exist on disk as well but referenced in the project file. Go to your source control software like Perforce, and it should mark these files which don't exist on disk in a different color scheme. Perforce shows them with a black lock on them. These are your missing references. Now you have a list of them all, and you can delete all of them from your project file using Notepad and your project would not complain about being out of date.
For me it was the presence of a non-existing header file on "Header Files" inside the project. After removing this entry (right-click > Exclude from Project) first time recompiled, then directly
========== Build: 0 succeeded, 0 failed, 5 up-to-date, 0 skipped ==========
and no attempt of rebuilding without modification was done. I think is a check-before-build implemented by VS2010 (not sure if documented, could be) which triggers the "AlwaysCreate" flag.
If you are using the command-line MSBuild command (not the Visual Studio IDE), for example if you are targetting AppVeyor or you just prefer the command line, you can add this option to your MSBuild command line:
/fileLoggerParameters:LogFile=MyLog.log;Append;Verbosity=diagnostic;Encoding=UTF-8
As documented here (warning: usual MSDN verbosity). When the build finishes, search for the string will be compiled in the log file created during the build, MyLog.log.
I'm using Visual Studio 2013 Professional with Update 4 but didn't find resolution with any of the other suggestions, however, I did manage to resolve the issue for my Team project.
Here's what I did to cause the problem -
Created a new class object (Project -> Add Class)
Renamed the file via Solution Explorer and clicked yes when asked if I wanted to automatically rename all references to match
Here's what I did to solve the problem -
Go to Team Explorer Home
Click Source Control Explorer
Drill into the folder where all of the class/project files are
Found the ORIGINAL filename in the list and deleted it via right-click
Build
If this is the case for you then just be extra sure that you're deleting the phantom file rather than the actual one you want to keep in the project.
I had this problem and found this:
http://curlybrace.blogspot.com/2005/11/visual-c-project-continually-out-of.html
Visual C++ Project continually out-of-date (winwlm.h macwin32.h rpcerr.h macname1.h missing)
Problem:
In Visual C++ .Net 2003, one of my projects always claimed to be out of date, even though nothing had changed and no errors had been reported in the last build.
Opening the BuildLog.htm file for the corresponding project showed a list of PRJ0041 errors for these files, none of which appear on my system anywhere:
winwlm.h macwin32.h rpcerr.h macname1.h
Each error looks something like this:
MyApplication : warning PRJ0041 : Cannot find missing dependency 'macwin32.h' for file 'MyApplication.rc'.
Your project may still build, but may continue to appear out of date until this file is found.
Solution:
Include afxres.h instead of resource.h inside the project's .rc file.
The project's .rc file contained "#include resource.h". Since the resource compiler does not honor preprocessor #ifdef blocks, it will tear through and try to find include files it should be ignoring. Windows.h contains many such blocks. Including afxres.h instead fixed the PRJ0041 warnings and eliminated the "Project is out-of-date" error dialog.
In my case one of the projects contains multiple IDL files. The MIDL compiler generates a DLL data file called 'dlldata.c' for each of them, regardless of the IDL file name. This caused Visual Studio to compile the IDL files on every build, even without changes to any of the IDL files.
The workaround is to configure a unique output file for each IDL file (the MIDL compiler always generates such a file, even if the /dlldata switch is omitted):
Right-click the IDL file
Select Properties - MIDL - Output
Enter a unique file name for the DllData File property
I spent many hours spent tearing out my hair over this. The build output wasn't consistent; different projects would be "not up to date" for different reasons from one build to the next consecutive build.
I eventually found that the culprit was DropBox (3.0.4). I junction my source folder from ...\DropBox into my projects folder (not sure if this is the reason), but DropBox somehow "touches" files during a build. Paused syncing and everything is consistently up-to-date.
There are quite a few potential reasons and - as noted - you need to first diagnose them by setting MSBuild verbosity to 'Diagnostic'. Most of the time the stated reason would be self explanatory and you'd be able to act on it immediatelly, BUT occasionally MSBuild would erroneously claim that some files are modified and need to be copied.
If that is the case, you'd need to either disable NTFS tunneling or duplicate your output folder to a new location. Here it is in more words.
This happened to me multiple times and then went away, before I could figure out why. In my case it was:
Wrong system time in the dual boot setup!
Turns out, my dual boot with Ubuntu was the root cause!! I've been too lazy to fix up Ubuntu to stop messing with my hardware clock. When I log into Ubuntu, the time jumps 5 hours forward.
Out of bad luck, I built the project once, with the wrong system time, then corrected the time. As a result, all the build files had wrong timestamps, and VS would think they are all out of date and would rebuild the project.
Most build systems use data time stamps to determine when rebuilds should happen - the date/time stamp of any output files is checked against the last modified time of the dependencies - if any of the dependencies are fresher, then the target is rebuilt.
This can cause problems if any of the dependencies somehow get an invalid data time stamp as it's difficult for the time stamp of any build output to ever exceed the timestamp of a file supposedly created in the future :P
For me, the problem arose in a WPF project where some files had their 'Build Action' property set to 'Resource' and their 'Copy to Output Directory' set to 'Copy if newer'. The solution seemed to be to change the 'Copy to Output Directory' property to 'Do not copy'.
msbuild knows not to copy 'Resource' files to the output - but still triggers a build if they're not there. Maybe that could be considered a bug?
It's hugely helpful with the answers here hinting how to get msbuild to spill the beans on why it keeps building everything!
If you change the Debugging Command arguments for the project, this will also trigger the project needs to be rebuilt message. Even though the target itself is not affected by the Debugging arguments, the project properties have changed. If you do rebuild though, the message should disappear.
I had a similar issue with Visual Studio 2005, and my solution consisted of five projects in the following dependency (first built at top):
Video_Codec depends on nothing
Generic_Graphics depends on Video_Codec
SpecificAPI_Graphics depends on Generic_Graphics
Engine depends on Specific_Graphics
Application depends on Engine.
I was finding that the Video_Codec project wanted a full build even after a full clean then rebuild of the solution.
I fixed this by ensuring the pdb output file of both the C/C++ and linker matched the location used by the other working projects. I also switched RTTI on.
Another one on Visual Studio 2015 SP3, but I have encountered a similar issue on Visual Studio 2013 a few years back.
My issue was that somehow a wrong cpp file was used for precompiled headers (so I had two cpp files that created the precompiled headers). Now why did Visual Studio change the flags on the wrong cpp to 'create precompiled headers' without my request I have no clue, but it did happen... maybe some plugin or something???
Anyway, the wrong cpp file includes the version.h file which is changed on every build. So Visual Studio rebuilds all headers and because of that the whole project.
Well, now it's back to normal behavior.
I had a VC++ project that was always compiling all files and had been previously upgraded from VS2005 to VS2010 (by other people). I found that all cpp files in the project except StdAfx.cpp were set to Create (/Yc) the precompiled header. I changed this so that only StdAfx.cpp was set to create the precompiled header and the rest were set to Use (/Yu) the precompiled header and this fixed the problem for me.
I'm on Visual Studio 2013 and just updated to the Windows 10 May 2019 update and compiling suddenly had to be redone every time, regardless of changes. Tried renaming the pch to ProjectName instead of TargetName, looked for missing files with the detailed log and that Python script, but in the end it was my time was not synced with MS's servers (by like milliseconds).
What resolved this for me was
"Adjust date and time" in the control panel
"Sync Now"
Now my projects don't need to be recompiled for no reason.
I think that you placed some newline or other whitespace. Remove it and press F5 again.
The .NET projects are always recompiled regardless. Part of this is to keep the IDE up to date (such as IntelliSense). I remember asking this question on an Microsoft forum years ago, and this was the answer I was given.