General troubleshooting

This appendix offers help with common issues you might encounter while using Linaro Forge.

Also, check that you have the latest version of the product on the Linaro Forge Downloads page.

• GUI cannot connect to an X Server
  • Related information
• Licenses
  • License error
  • No licenses found
• F1 cannot display this document
  • Corrupt files prevent Qt Assistant starting
  • Solution
• MPI not detected
  • MPI settings not configured
• Starting a program
  • Starting scalar programs
  • Starting scalar programs with aprun
  • Starting scalar programs with srun
  • Problems when you start an MPI program
  • Starting multi-process programs
  • No shared home directory
  • Linaro DDT or Linaro MAP cannot find your hosts or the executable
  • Linaro Forge libraries conflict with program libraries
  • The progress bar does not move and Linaro Forge times out
  • Resource temporarily unavailable
• Attaching
  • The system does not allow connecting debuggers to processes (Fedora, Ubuntu)
  • The system does not allow connecting debuggers to processes (Fedora, Red Hat)
  • Running processes not shown in the attach window
• Source code view
  • No variables or line number information
  • Source code does not appear when you start Forge
  • Code folding does not work for OpenACC/OpenMP pragmas
• Input/Output
  • Output to stderr does not display
  • Unwind errors
• Controlling a program
  • Program jumps forwards and backwards when stepping through
  • Linaro DDT might stop responding when using the Step Threads Together option
  • Stepping into Coroutines
• Evaluating variables
  • Some variables cannot be viewed when the program is at the start of a function
  • Incorrect values printed for Fortran array
  • Evaluating an array of derived types, containing multiple-dimension arrays
  • C++ STL types are not pretty printed
• Memory debugging
  • The View Pointer Details window says a pointer is valid but does not show you which line of code it was allocated on
  • mprotect fails error when using memory debugging with guard pages
  • Allocations made before or during MPI_Init show up in Current Memory Usage but have no associated stack back trace
  • Deadlock when calling printf or malloc from a signal handler
  • Program runs more slowly with Memory Debugging enabled
• MAP specific issues
  • MPI wrapper libraries
  • Thread support limitations
  • No thread activity while blocking on an MPI call
  • I am not getting enough samples
  • I just see main (external code) and nothing else
  • Linaro MAP reports time spent in a function definition
  • Linaro MAP does not correctly identify vectorized instructions
  • Linking with the static Linaro Forge sampler library fails with FDE overlap errors
  • Linking with the static Linaro Forge sampler library fails with an undefined references to “__real_dlopen”
  • Linaro MAP adds unexpected overhead to my program
  • Linaro MAP takes an extremely long time to gather and analyze my OpenBLAS-linked application
  • Linaro MAP over-reports MPI, Input/Output, accelerator or synchronization time
  • Linaro MAP collects very deep stack traces with boost::coroutine
• Excessive memory use
  • Reduce processes per node
  • Reduce debug information
  • Profiling settings