Search in
Sort by:

Question Status:

Search help

  • Simple searches use one or more words. Separate the words with spaces (cat dog) to search cat,dog or both. Separate the words with plus signs (cat +dog) to search for items that may contain cat but must contain dog.
  • You can further refine your search on the search results page, where you can search by keywords, author, topic. These can be combined with each other. Examples
    • cat dog --matches anything with cat,dog or both
    • cat +dog --searches for cat +dog where dog is a mandatory term
    • cat -dog -- searches for cat excluding any result containing dog
    • [cats] —will restrict your search to results with topic named "cats"
    • [cats] [dogs] —will restrict your search to results with both topics, "cats", and "dogs"

Office Holiday

Epic Games' offices will be on holiday from June 22nd to July 7th. During this period support will be limited. Our offices will reopen on Monday, July 8th. 

[Bug Report] Clang 3.5 compilation error with -Werror and -Wshado

It seems Clang is a little rabid in terms of variable naming - because "-Wshadow" is set, attempting to compile a C++ class on Linux using Clang 3.5 results in a warning when a function parameter has the same name as data member. As the flag "-Werror" is also set, this warning gets promoted to a full-blown error and interrupts the build.

Dropping "-Werror" from the compilation arguments should theoretically make these issues a visual log annoyance instead of a blocking issue. GCC has had the same issue as a bug report, but has apparently fixed it.


The provided sample code below compiles fine on Windows 7 using Visual Studio 2013 Community, but fails with the following error on Linux Mint 17.2, using Qt Creator and Clang 3.5.

Sample code:

 #pragma once
 #include "GameProject.h"
 #include "MemoryElement.generated.h"
 struct GAMEPROJECT_API FMemoryElement
     UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Memory")
         FString KeyName;
     UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Memory")
         FString Data;
         KeyName = "";
         Data = "";
     FMemoryElement(FString KeyName, FString Data)
         this->KeyName = KeyName;
             this->Data = Data;

Compilation Error:

 In file included from /home/jarl/Programming/Unreal Projects/GameProject 4.8/Intermediate/Build/Linux/x86_64-unknown-linux-gnu/UE4Editor/Inc/GameProject/GameProject.generated.cpp:9:
 In file included from ../../../Unreal Projects/GameProject 4.8/Intermediate/Build/Linux/x86_64-unknown-linux-gnu/UE4Editor/Inc/GameProject/GameProject.generated.dep.h:21:
 ../../../Unreal Projects/GameProject 4.8/Source/GameProject/Dialogue/MemoryElement.h:27:25: error: declaration shadows a field of 'FMemoryElement' [-Werror,-Wshadow]
         FMemoryElement(FString KeyName, FString Data)
 ../../../Unreal Projects/GameProject 4.8/Source/GameProject/Dialogue/MemoryElement.h:16:11: note: previous declaration is here
                 FString KeyName;
 ../../../Unreal Projects/GameProject 4.8/Source/GameProject/Dialogue/MemoryElement.h:27:42: error: declaration shadows a field of 'FMemoryElement' [-Werror,-Wshadow]
         FMemoryElement(FString KeyName, FString Data)
 ../../../Unreal Projects/GameProject 4.8/Source/GameProject/Dialogue/MemoryElement.h:19:11: note: previous declaration is here
                 FString Data;

While workarounds are available (renaming member variables to have a trailing underscore, renaming the function parameter), it is a common idiom to give function parameters the same name as the variable they initialize or affect.

 Distro: Linux Mint 17.2
 Compiler: Clang 3.5
 IDE: Qt Creator
 Unreal Engine: 4.8.3 (Github 4.8 branch source build)

Product Version: UE 4.8
more ▼

asked Aug 25 '15 at 10:26 AM in Linux

avatar image

808 39 30 65

avatar image Jargon Aug 26 '15 at 06:34 PM
(comments are locked)
10|2000 characters needed characters left
Viewable by all users

0 answers: sort voted first
Be the first one to answer this question
toggle preview:

Up to 5 attachments (including images) can be used with a maximum of 5.2 MB each and 5.2 MB total.

Follow this question

Once you sign in you will be able to subscribe for any updates here

Answers to this question