Windows error 0xFFFFFFFD, -3

Printing negative values as hex in python

I have the following code snippet in C++: for (int x = -4; x < 5; ++x) printf("hex x %d 0x%08X\n", x, x); And its output is hex x -4 0xFFFFFFFC hex x -3 0xFFFFFFFD hex x -2 0xFFFFFFFE hex x -1 0xFFFFFFFF hex x 0 0x00000000 hex x 1 [...] read more

What is clang trying to do optimizing this simple recursive algorithm?

Upon writing an answer to this question: Using variable vs. using number I ran clang x86 9.0.0/trunk with -O3 to see if it could do tail-call optimization of this simple code: int faculty1 (const unsigned int n) { return n == 1 ? n : n * faculty1(n - 1); [...] read more

Different performance of "if" and "if else" in Java

I noticed that if else / ternary (condition ? a : b) assigment is faster than conditional assigment in if only statement. I performed JMH benchmarks on different JDKs but i will focus on JDK 12. (ops / sec, higher is better) JMH benchmark [https://i.stack.imgur.com/nxuCG.png] Source code: @State(Scope.Benchmark) public class [...] read more

Debugging 'terminate called after throwing an instance of ...', when the exception _should_ have been caught

I'm debugging an issue which only seems to happen on Solaris (we test on Windows, Linux, OSX, Solaris, HP-UX, and AIX). Our code throws an exception (which is totally expected), and this results in the 'terminate called after throwing an instance of ...' message being printed, and the process being [...] read more

What is vmovdqu doing here?

I have a Java loop that looks like this: public void testMethod() { int[] nums = new int[10]; for (int i = 0; i < nums.length; i++) { nums[i] = 0x42; } } The assembly I get is this: 0x00000001296ac845: cmp %r10d,%ebp 0x00000001296ac848: jae 0x00000001296ac8b4 0x00000001296ac84a: movl $0x42,0x10(%rbx,%rbp,4) 0x00000001296ac852: inc [...] read more

JBoss spamming XA Recovery warnings

I'm running a JPA/Spring application that connects to multiple XA enabled datasources on Microsoft SQL Server. Everything works just fine, with global transactions correctly starting and rolling back as needed... But, every now and then JBoss goes wild and starts spamming the following warning every few seconds: 10:25:22,524 WARN [com.arjuna.ats.jta] [...] read more

Handling MouseWheel event in a WPF custom control

I have am making a map editor for a game which has a user control that has an image. Inside that control I attached the MouseWheel event to it, but I've noticed two issues that I hope to have a better understanding of why it behaves the way it does [...] read more

Strange behavior with << operator

When dealing with the C# shift operators, I encountered a unexpected behavior of the shift-left operator. Then I tried this simple function: for (int i = 5; i >= -10; i--) { int s = 0x10 << i; Debug.WriteLine(i.ToString().PadLeft(3) + " " + s.ToString("x8")); } With this result: 5 00000200 [...] read more

C# Com Enum and VB6

Hi I created C# Exe Com Server and refer it from VB6 application. The problem is that all the enums are exposed with "strange name" in the vb app: EnumName_EnumeItem, while reffered from then VB6 code as EnumName.EnumItem. The VB6 application code cannot be modified. Wondering around I saw I [...] read more

W3WP recycle return codes

I have an IIS6 machine, running multiple web applications. Once in a while, IIS recycles W3WP. When i look at the error codes, W3WP.exe usually exits with return code -2 (0xfffffffe) but one in a while it exits with -3 (0xfffffffd). While the end result is the same, i was [...] read more

Normalizing a two complement number

I am working on some Tensilica processor and I don't understand the normalization process. NSA - Normalized Shift Amount Usage: NSA at, as NSA calculates the left shift amount that will normalize the twos complement contents of address register as and writes this amount (in the range 0 to 31) [...] read more

Data overriden when branch to PendSV

I have a little "os" for an arm cortex m4. I implemented a wait function. But since then somehow, the context switch is corrupted. When stepping through the instructions i noticed, that for whatever reason the current_task variable gets overriden at entering the PendSV interrupt. These are global variables volatile [...] read more

How can I trace the cause of an invalid PC fault on Cortex M3?

I have an STM32 Cortex M3 that is experiencing an intermittent invalid PC (INVPC) fault. Unfortunately it takes a day or more to manifest and I don't know the cause. I have the device paused in the debugger after the fault happened. The INVPC flag is set. The stacked registers [...] read more

Are ARM Cortex-M0 Stacking Registers Saved On $psp or $msp During Hardfault?

I have an issue where my Cortex-M0 is hard faulting, so I am trying to debug it. I am trying to print the contents of the ARM core registers that were pushed to the stack when the hard fault occurred. Here is my basic assembly code: __attribute__((naked)) void HardFaultVector(void) { [...] read more

Running the nnlib test app on the Hexagon HVX DSP

I have tried different versions of nnlibs at codeaurora and used SDK 3.0, 3.2 and 3.3.3 to compile and test them. The closest I got was to use the commit version 7321d49318a33a99e978b18411adee43df7ddaea (Jan 2018) with SDK 3.3.3 and while running the graph_app I receive this helper: $ adb shell /data/graph_app [...] read more

what is the program entry label _iar_program_start use for in IAR Workbench for ARM?

I am developping a firmware on an ARM CORTEX M3 processor, with IAR IDE (v6.50). I am wondering the usefullness of the label used for the program entry. I explain. On the ARM platform, when the chip is reset the PC is loaded with one of the entry of the [...] read more

Task switching on Cortext-M3 crashes after IRQ

I've used an exokernel model for my ARM Cortex-M3 OS. When a task wants to read from a UART it calls a library function, which, if there's no data, makes a SVC call to block the task (which causes the kernel to put the task in the wait queue for [...] read more

Understanding "not" on booleans

My question seems simple, but I've been perplexed about it: bool myBool = TRUE; if (myBool) printf("1 myBool = true\n"); else printf("1 myBool = false\n"); myBool = !myBool; if (myBool) printf("2 myBool = true\n"); else printf("2 myBool = false\n"); printf("%d\n", TRUE); printf("%d\n", FALSE); All of that outputs: 1 myBool = [...] read more

Access GDT after data segment had been set?

This is a really stupid question, but I can't seem to solve it. In my OS the GDT is setup via assembly code that links upped with the kernel. When that happens, of course the data segment and code segment are set up when the GDT is loaded. The this [...] read more

Continue after assert with Android NDK and GDB

Is it possible to trigger an GDB break from C++ in an Android NDK program which still allows the program to resume afterwards? Meaning, I hit the assert causing GDB to halt the program, and I want to be able to press the "Play" button in Eclipse to resume the [...] read more

error /var/tmp/kdecache is owned by uid 1000 instead of uid 0

I'm coding a Qt 4.8 program (http://code.google.com/p/image-feature-detector/) with NetBeans 7.1 in Kubuntu 12.04 (although with Kubuntu 11.10 the same happens) and I'm getting a maddening error when I try to run the executable compiled. The program compiled and run perfectly but suddenly one day I got this error when, after [...] read more

OpenOCD connection with STM32F1x and ST-Link

I am using STM32F103. I want to use OpenOCD to flash STM32. I was using keil but I want to shift to arm-gcc compiler. I can compile the code for the controller. But now I want to flash it using OpenOCD. I was able to manage its configurations. Here are [...] read more

What determines where the exception frame goes on Cortex-M4?

I'm struggling with an exception stack frame writing over my local/automatic/stack variables. I'm using FreeRTOS 8.2.1 and Microchip ASF for SAM4L Developing with Eclipse MCU 2018/09 and Segger J-Link 6.40. [EDIT] The very first time through the loop, r7 has a different value (0x200044D0), which looks like it might be [...] read more

Tail Call Optimization (TCO) in Clang on O2

I was playing with Tail Call Optimization (TCO) and various optimization levels in clang on godbolt. I have the very simple function (lifted from here): int factorial (int x, int y){ if (x==0) return y; else return factorial(x-1,y*x); } If I set -O1, all is good and I understand the [...] read more

firebaseAuth.logout workf for menu activity but not for profile activity

I may entangled myself in this but I can't seem to see any reason why this doesn't work. In the MenuActivity the menu items and their functionalities work fine. Log out works perfectly. When I extent the MenuActivity to the ProfileActivity, for some reason the log out button doesn't work [...] read more

Confusion with comparing negative integers

I've begun to study assembly and I have some difficult with a sample program. I wrote a macro that would find the minimum in an array: %macro min 3 mov ecx, dword[%2] mov r12, 0 lea rbx, [%1] movsx eax, word[rbx+r12*4] ; inizializza il minimo con il primo elemento dell'array [...] read more

Get Currently Opened Word Document from Process

The goal is to get the full path to the document opened in an instance of Microsoft Word that I have a process reference for. Pseudocode Example: Process myWordProcess = something; // This is my process reference DocumentInformation docInfo = SomeNamespace.GetDocumentInformation(myWordProcess); string documentPath = docInfo.FullName; // "C:\User\Foo\Documents\Test.docx" The starting point [...] read more

I don't understand why the behavior of the 1's complement in C is different when acting on a number vs acting on a variable storing a number

Output of the following code: test1: 0x00000002 0b00000010 (1 bytes) test2: 0x000000fd 0b11111101 (1 bytes) ~test1: 0xfffffffd 0b4294967285 (4 bytes) I don't understand why doing ~(test1) is different from ~(0x02) since test1=0x02 and everything is unsigned. It appears that ~(test1) does the proper complement but then adds 3 bytes of [...] read more

Is there any way to represent the range 0x80-0xFF as a single byte in Java?

I have been fighting with this for a while, I'm trying to calculate a checksum for a byte[] as the 1s complement of the 1s complement sum of 16 bit words in the array. The sum is fairly easy (though I'm sure I could be more efficient) but when I [...] read more

receiving from remote server giving junk characters?

I am trying to write a telnet client to connect to following server: 198.182.241.14 (hosted by: Pittsburg State University, Kansas, USA) - login: library I have successfully connected through following code; sd = socket(AF_INET, SOCK_STREAM, 0); struct sockaddr_in sin; memcpy(&sin.sin_addr.s_addr, host->h_addr, host->h_length); sin.sin_family = AF_INET; sin.sin_port = htons(portno); if (connect(sd, [...] read more

c++ : filling map of maps via map instance allocation from a vector of maps

part 2 to my : https://stackoverflow.com/questions/21780627/c-map-of-maps-typedef-doubts-queries I then move ahead to create vectors (resizeable) of InnerMap, MiddlMap and do the following: InnerMap inmap; vector<InnerMap> vec_inmap; vec_inmap.resize (8); int vec_inmap_sz = 8; vec_inmap.insert (vec_inmap.end (), 8, inmap); vector<InnerMap>::iterator vec_inmap_it = vec_inmap.begin (); InnerMap::iterator inmap_it; MiddlMap mdmap, curr_mdmap; vector<MiddlMap> vec_mdmap; vec_mdmap.resize (8); [...] read more

Analyzing Asp.net deadlock crash dump

I'm having a deadlock on my asp.net. I don't know where it comes from (what function), not talking about where in that function. I generated dump file using adplus (http://support.microsoft.com/?ID=828222) and then used Debug Diag & windbg to find the problem. ( no success yet.. :( ) I'm out of [...] read more

What could cause malloc to initialise memory?

I am writing code to use a library called SCIP (solves optimisation problems). The library itself can be compiled in two ways: create a set of .a files, then the binary, OR create a set of shared objects. In both cases, SCIP is compiled with it's own, rather large, Makefile. [...] read more

How to analyse the invalid PC fault on Cortex-M3?

SoC：SmartFusion2 Processor：Cortex-M3 OS: FreeRTOS v9.0.0 IDE:SoftConsole v4.0 During the running of the software, an exception occurs and enter HardFault with invalid PC.I don't know the cause and how to trace. /*============================================================================== * HardFault_Handler */ .weak HardFault_Handler .type HardFault_Handler, %function HardFault_Handler: TST LR, #4 ITE EQ MRSEQ R0, MSP MRSNE R0, [...] read more

Why use a bitwise not in MIPS instead of using exactly value?

I'm trying to learn MIPS assembly, but I'm a bit confused about an example of MIPS assembly I have found. #Socket Domain - AF_INET (2) li $t4, 0xFFFFFFFD #-3 not $a0, $t4 #Socket Type - SOCK_STREAM (2 for mips) not $a1, $t4 #Socket Protocol - 0 slti $a2, $zero, 0xFFFF [...] read more

Cortex M3 - Calling a SVC inside a C function, and returning to thread mode

I am writing System Calls, as recommended by Joseph Yiu (M3 Guide), by taking the arguments from the stack. The Assembly SVC Handler is like: SVC_Handler: MOV R0, #0 MSR CONTROL, R0 CMP LR, #0xFFFFFFFD BEQ KernelEntry B KernelExit KernelEntry: <save current user stack> B svchandler_main KernelExit: <code to restore [...] read more

How can I assemble this MIPS shellcode?

I have some code from GitHub that I need to compile for a PoC. I need to change the IP address (which I can do), but I cannot actually do the compilation after. Any suggestions what compiler will work? Ideally if I assemble what's there I should get the same [...] read more

Why are no dts pts written to my mp4 container

Based on my (self-answered) question here Muxing AVPackets into mp4 file - revisited, I have to ask, what could be the reason why there are no values written for pts/dts in the resulting mp4 container. I examined the container file with the tool MediaInfo. I observe that only the very [...] read more

STM32F103 priorities to handle nested interrupts

I could find a problem related to NVIC_Init in STM32F10x library related to priorities to handle nested interrupts. We know that any interrupt with a priority value equal or higher than BASEPRI ( 11 in our case) can call FromISR() FreeRTOS API functions. FreeRTOS uses 15 level ( the lowest [...] read more

StorageException has occurred.Object does not exist at location.Code: -13010 HttpResult: 404 in android studio logcat

Here is my logcat: > 2018-11-04 08:54:03.257 20512-20582/com.example.nabil.logindemo > E/StorageException: StorageException has occurred. Object does not exist at > location. Code: -13010 HttpResult: 404 2018-11-04 08:54:03.268 > 20512-20582/com.example.nabil.logindemo E/StorageException: { "error": { > "code": 404, "message": "Not Found. Could not get object" }} > java.io.IOException: { "error": { "code": 404, [...] read more

Openvas Erroneous or missing signature for checksums file (null)

My exp.nasl insstr("aaaaaaaaaaa", "bb", 3, 0xfffffffd); run code $sudo openvas-nasl ali.nasl I get this error when I run exp.nasl with openvas base gpgme-Message: Setting GnuPG dir to '/etc/openvas/gnupg' base gpgme-Message: Using OpenPGP engine version '2.1.11' Erroneous or missing signature for checksums file (null) read more

Why is this expression faster than one of its components on its own?

Why is (i&1) | ((i&mostSig)?onesComp:0), where all three variables are integers, faster than i&1 on its own when compiled on GCC without optimisation? The first expression obviously has to evaluate i&1 and then OR it with ((i&shift)?oneortwo:0), so I would expect it to be faster than i%2 but slower than [...] read more

Making asynchronous requests using Unirest returns ZipException: Not in GZIP format

I want to make asynchronous requests to my server using Unirest. This is my test code: public void unirestTest() throws InterruptedException, ExecutionException { Unirest.get("https://jsonplaceholder.typicode.com/posts/1") .header(CONTENT_TYPE, APPLICATION_JSON.toString()) .asJsonAsync(new Callback<JsonNode>() { public void failed(UnirestException e) { e.printStackTrace(); } public void completed(HttpResponse<JsonNode> response) { System.out.println("OK"); } public void cancelled() { System.out.println("Request has been [...] read more

Unable to start activity ComponentInfo in Android after crash

I don't know where this error comes from. It appears when I start the app and crashes! Error message and stack trace: 09-16 17:57:32.022 2441-2441/com.example.tobias.uebung1 E/AndroidRuntime﹕ FATAL EXCEPTION: main Process: com.example.tobias.uebung1, PID: 2441 java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.tobias.uebung1/com.example.tobias.uebung1.main}: android.content.res.Resources$NotFoundException: String resource ID #0xfffffffd at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2416) at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2476) at android.app.ActivityThread.-wrap11(ActivityThread.java) [...] read more

Casting a hex number under unchecked scope

Well I am trying to understand how negative numbers work and trying to cast a hex number as we can see below to a singed integer, but the question is why does this work only under "unchecked" scope? unchecked { signedInt = (int)0xffffffff; // -1 (1111........ 1111) signedInt = (int)0xfffffffd; [...] read more

MAPIInitialize fails when running as a service and when Outlook is open

We have an application that can run as a Windows service (or as a user mode app). As part of it's processing, it launches a second executable that interacts with MAPI to read the contents of an MSG file. The executable is 32 bit. Office is 32 bit. So far, [...] read more

simple struct dereference trigger ARM hard_fault hardware exception

I've been debugging this for many hours now. My application is an embedded program running on the CC2650 ARM M3 processor using the TI RTOS. This line of c generates an ARM hard_fault exception (LD - link register set to 0xFFFFFFFD): leaseStartMessageForReplay = *leaseStartMessage; The code simply dereferences the leaseStartMessage [...] read more

hard fault inv state part 2

I am unsure how to debug this error. I am getting a hard fault exception that is taking me to an infinite loop for my stm32 eval2 board when I try to use the camera. I think that I am supposed to look at the registers for this problem, but [...] read more

MediaPlayer start->stop->start for MIDI files

I am seeing a problem with MediaPlayer, trying to do the next sequence start()->stop()->start() for MIDI files gives me an error. By looking at the MediaPlayer state diagram, the sequence should work with the next code: void experiment() throws IllegalArgumentException, SecurityException, IllegalStateException, IOException { Context context = this; int resid [...] read more