similar to: Building R package: “Found 'rand', possibly from 'rand' (C)” NOTE when checking package

Dear all, In our LLVM-based compiler pipeline a major part of code generation is taken into application runtime. One side-effect of this organization is a need to be very careful about using code that might diverge application state. And we found that simple generation of temporary files over LLVM APIs introduces random noise into the program result. There reason is that LLVM's

Hi everyone, sorry if this has been answered before - I caught a whiff of a discussion about c's rand() function in a mailing list archive, but couldn't find a definitive answer. I'm trying to do a simple CS project on my machine where I generate two sets of values in parallel using rand() and am running into infinite loops of values, and couldn't figure out why, so I wrote a test

Agreed, done. One thing I'm not sure about is this statement in docs: POSIX.1-2008 marks *rand_r*() as obsolete. - And... what is the replacement? 2012/12/1 Justin Holewinski <justin.holewinski at gmail.com> > If we're keeping the state locally now, perhaps we should store it in a > per-thread variable. I know rand() isn't thread safe to begin with, but it > seems

If we're keeping the state locally now, perhaps we should store it in a per-thread variable. I know rand() isn't thread safe to begin with, but it seems like rand_r() can be since it should keep no external state. On Sat, Dec 1, 2012 at 11:17 AM, Dmitry Mikushin <dmitry at kernelgen.org>wrote: > Dear all, > > In our LLVM-based compiler pipeline a major part of code

Correcting my patch, reg. __thread stuff I'm not very familiar with. - D. 2012/12/1 Dmitry Mikushin <dmitry at kernelgen.org> > Agreed, done. > > One thing I'm not sure about is this statement in docs: > > POSIX.1-2008 marks *rand_r*() as obsolete. > > - And... what is the replacement? > > > 2012/12/1 Justin Holewinski <justin.holewinski at

Erik, I was thinking of doing this: export MALLOC_PERTURB_=$(awk 'BEGIN { srand(); print int(rand() * 32767 % 255 + 1) }') Or would you prefer using 'date'? On Tue, Mar 19, 2013 at 10:22 PM, Erik de Castro Lopo <mle+la at mega-nerd.com>wrote: > Jesse Weinstein wrote: > > > The subject line mostly says it all, but for reference, having #!/bin/sh > causes

On Tue, Mar 12, 2013 at 10:23 AM, Renato Golin <renato.golin at linaro.org>wrote: > On 12 March 2013 16:48, Daniel Dunbar <daniel at zuster.org> wrote: > >> The former mode is historically what the test suite did, the latter mode >> is substantially faster (and independent of bugs in the native CC). >> > > Yes, I agree this is better for many cases, but

Here I am again... I missed that in the previous diff, they are the usual missing <algorithm> and the std:: namespace missing in sort, find, make_pair. Alkis can you please give them an eye when you have time? The next major problem is that VC has only int rand(void) void srand( int seed ) So I donno how to compile the ExecutionEngine/Interpreter/ExternalFunctions.cpp that refers to the

These calls are in ExternalCalls.cpp, they are platform dependent calls, so maybe llvm should consider including it's own implementation of a random number generator? For the time being I just replaced with calls to srand and rand like Paolo also did, but it needs to be fixed... m.

Hmm, I guess I need a sys::Math::getRandom() function that uses a "good" random number generator on the given platform. I'll make a note of this and tuck it away for future implementation. Reid. Chris Lattner wrote: > On Tue, 28 Sep 2004, Paolo Invernizzi wrote: > > >>The next major problem is that VC has only >> >>int rand(void) >>void srand(

On Tue, 28 Sep 2004, Paolo Invernizzi wrote: > The next major problem is that VC has only > > int rand(void) > void srand( int seed ) > > So I donno how to compile the > ExecutionEngine/Interpreter/ExternalFunctions.cpp that refers to the > drand48 srand48 lrand48 etc series... > For now I hacked them, like > > double drand48(void) { return (float) rand() /

Dear R experts, we are preparing an R-package to compute the Oja Median which contains some C++ code in which random numbers are needed. To generate the random numbers we use the following Mersenne-Twister implementation: // MersenneTwister.h // Mersenne Twister random number generator -- a C++ class MTRand // Based on code by Makoto Matsumoto, Takuji Nishimura, and Shawn Cokus // Richard J.

Morten, have a look at the http://mail.cs.uiuc.edu/pipermail/llvmdev/2004-September/002235.html thread... On Oct 19, 2004, at 2:40 PM, Morten Ofstad wrote: > These calls are in ExternalCalls.cpp, they are platform dependent > calls, so maybe llvm should consider including it's own implementation > of a random number generator? For the time being I just replaced with > calls

I don't know if __thread is well-supported enough on compilers to use in LLVM core code. LLVM has its own support class: ThreadLocal http://llvm.org/doxygen/classllvm_1_1sys_1_1ThreadLocal.html And if randr_r() is obsolete, I'm not sure we should be using it. What platforms have you tested this on? Is it available on Windows, Mac, BSDs? If not touching global state is important

Hi all, I am processing DWARF line and column information in (x86 and ARM) executables in order to produce a mapping from the machine instructions back to the original source code (C/C++). Using the line numbers is quite straightforward ("libdwarf" [1] is doing the work me.) But when comparing the column numbers (extracted from the DWARF line table) with the corresponding source

On Wed, 29 Sep 2004, Reid Spencer wrote: > > On Tue, 28 Sep 2004, Paolo Invernizzi wrote: > >>The next major problem is that VC has only > >> > >>int rand(void) > >>void srand( int seed ) > >> > >>So I donno how to compile the > >>ExecutionEngine/Interpreter/ExternalFunctions.cpp that refers to the > >>drand48 srand48

On 31.05.2011 19:22, Devang Patel wrote: > > On May 30, 2011, at 11:11 AM, trash-stuff at gmx.de > <mailto:trash-stuff at gmx.de> wrote: > >> Hi all, >> >> I am processing DWARF line and column information in (x86 and ARM) >> executables in order to produce a mapping from the machine >> instructions back to the original source code (C/C++). Using

On May 30, 2011, at 11:11 AM, trash-stuff at gmx.de wrote: > Hi all, > > I am processing DWARF line and column information in (x86 and ARM) executables in order to produce a mapping from the machine instructions back to the original source code (C/C++). Using the line numbers is quite straightforward ("libdwarf" [1] is doing the work me.) But when comparing the column numbers

Hi list, I keep on getting this "rand" word come up on my console. It shows up maybe one out 20 times I type in R console. I don't understand why it is coming up? > mean(variables) [1] -0.41 rand rand rand rand rand rand rand rand rand rand rand rand rand rand rand> mean(variables) > rm(list=ls()) rand rand rand rand rand rand rand rand rand rand rand rand rand

This takes advantage of glibc's MALLOC_PERTURB_. If you develop on glibc-based systems and don't yet set this via your shell's init scripts, add something like this to e.g., .bashrc: export MALLOC_PERTURB_=$(($RANDOM % 255 + 1)) This change ensures that it's enabled for anyone running "make check" and in particular for koji. There's probably documentation