optimization - C++ optimizer removal of object with side effects -

-

this not problem, concerned if code gets ported or change compilers.

i have code block

{     myclass myobj;    // copy other variables never touch myobj    .    . } // expect destructor called on myobj

where myobj never used in block code constructor has side effect , rely on destructor code of myclass executed @ close of block. works expected on current arm compiler optimization turned on.

my question is, there thing need do, declaring volatile or setting common attribute prevent optimizer detecting myobj unused variable or such.

this not c++11 compiler. said not problem did not want leave odd future bug else.

apart explicitly defined cases rvo (return value optimization), optimization not allowed change observable behaviour of program. optimizations must follow called "as-if" rule.


Comments

Post a Comment

Popular posts from this blog

Java 3D LWJGL collision -

-
i making 3d java game lwjgl library, , wondering how add collision detection, player not go through models. i using obj models. here objloader class, loads models: package renderengine; import java.io.bufferedreader; import java.io.file; import java.io.filenotfoundexception; import java.io.filereader; import java.util.arraylist; import java.util.list; import models.rawmodel; import org.lwjgl.util.vector.vector2f; import org.lwjgl.util.vector.vector3f; public class objloader { public static rawmodel loadobjmodel(string filename, loader loader){ filereader fr = null; try { fr = new filereader(new file("res/"+filename+".obj")); } catch (filenotfoundexception e) { system.err.println("couldn't load file!"); e.printstacktrace(); } bufferedreader reader = new bufferedreader(fr); string line; list<vector3f> vertices = new arraylist<vector3f...
Read more

spring - SubProtocolWebSocketHandler - No handlers -

-
i have ugly error during deploying spring app on jboss. 18:11:16,025 error [org.apache.catalina.core.containerbase.[jboss.web].[default-host].[/consumer]] (msc service thread 1-7) exception sending context initialized event listener instance of class org.springframework.web.context.contextloaderlistener: org.springframework.context.applicationcontextexception: failed start bean 'subprotocolwebsockethandler'; nested exception java.lang.illegalargumentexception: no handlers @ org.springframework.context.support.defaultlifecycleprocessor.dostart(defaultlifecycleprocessor.java:176) [spring-context-4.1.3.release.jar:4.1.3.release] @ org.springframework.context.support.defaultlifecycleprocessor.access$200(defaultlifecycleprocessor.java:51) [spring-context-4.1.3.release.jar:4.1.3.release] @ org.springframework.context.support.defaultlifecycleprocessor$lifecyclegroup.start(defaultlifecycleprocessor.java:346) [spring-context-4.1.3.release.jar:4.1.3.release] @ org.s...
Read more

methods - python can't use function in submodule -

-
my folder structure this: pythonstuff/ program.py modulea/ __init__.py foo.py bar.py here's code bar.py : def hello(): print("hello, world!") here's code program.py : #!/usr/bin/env python3 modulea import bar bar.hello() i run $ python3 program.py somehow error: file "program.py", line 3, in <module> bar.hello() attributeerror: 'module' object has no attribute 'hello' edit: __init__.py file empty. edit2: after trying realized had bar.py in root directory contained hello() method. bar.py in modulea/ directory empty. add it import os __all__ = [] module in os.listdir(os.path.dirname(__file__)): if module != '__init__.py' , module[-3:] == '.py': __all__.append(module[:-3]) the init .py files required make python treat directories containing packages; done prevent directories common name, such string, unintentionally hiding v...
Read more