The problem is ssize_t is not portable to Microsoft.
> On Sep 13, 2016, at 3:05 PM, Munson, Todd <[email protected]> wrote: > > > The write statement return type is ssize_t. For whatever reason its a signed > type > because it can return -1 on error. > > I would suggest using the ssize_t type for both and changing the "!=" to a "<" > which will abort if write either returns a negative or the number of bytes > written is not correct. > > Note: you will have problems if (ssize_t) (m*n*sizeof(double)) is negative > though, but that can be checked as well. > > Todd. > >> On Sep 13, 2016, at 2:50 PM, Satish Balay <[email protected]> wrote: >> >> This works.. >> >> Satish >> >> --------- >> >> diff --git a/src/mat/examples/tests/ex45.c b/src/mat/examples/tests/ex45.c >> index 63d0a30..37f68e3 100644 >> --- a/src/mat/examples/tests/ex45.c >> +++ b/src/mat/examples/tests/ex45.c >> @@ -72,7 +72,7 @@ void Store2DArray(int m,int n,double *a,const char >> *filename,int *fdd) >> vals[i+m*j] = a[j+i*n]; >> } >> } >> - if (write(fd,vals,m*n*sizeof(double)) != ((unsigned int) >> (m*n))*sizeof(double)) abort(); >> + if ((size_t)write(fd,vals,m*n*sizeof(double)) != >> (size_t)(m*n*sizeof(double))) abort(); >> free(vals); >> >> } >> @@ -94,7 +94,7 @@ void Store1DArray(int m,double *a,const char *filename,int >> *fdd) >> } >> if (write(fd,&classid,sizeof(int)) != sizeof(int)) abort(); >> if (write(fd,&m,sizeof(int)) != sizeof(int)) abort(); >> - if (write(fd,a,m*sizeof(double)) != ((unsigned int)m)*sizeof(double)) >> abort(); >> + if ((size_t)write(fd,a,m*sizeof(double)) != (size_t)(m*sizeof(double))) >> abort(); >> } >> >> >> On Tue, 13 Sep 2016, Satish Balay wrote: >> >>> I would tink if its typecast to same type - comparision would work.. >>> >>> if ((ssize_t)write(fd,vals,m*n*sizeof(double)) != >>> (ssize_t)(m*n*sizeof(double))) abort(); >>> >>> I'll give this a try... >>> >>> Satish >>> >>> On Tue, 13 Sep 2016, Barry Smith wrote: >>> >>>> >>>> I need help from someone who knows the subtleties of c++. We have a >>>> PETSc example that always compiles fine with C but generates annoying >>>> warnings with C++. I've tried many different variants to eliminate the >>>> warnings with no luck >>>> >>>> Any help is appreciated. >>>> >>>> Barry >>>> >>>> >>>> mpicxx -o ex45.o -c -Wall -Wwrite-strings -Wno-strict-aliasing >>>> -Wno-unknown-pragmas -fvisibility=hidden -g -O -fPIC >>>> -I/sandbox/petsc/petsc.clone-3/include >>>> -I/sandbox/petsc/petsc.clone-3/arch-linux-opt-cxx-quad/include >>>> -I/usr/include/mpich2 `pwd`/ex45.c >>>> /sandbox/petsc/petsc.clone-3/src/mat/examples/tests/ex45.c: In function >>>> ‘void Store2DArray(int, int, double*, const char*, int*)’: >>>> /sandbox/petsc/petsc.clone-3/src/mat/examples/tests/ex45.c:75:41: warning: >>>> comparison between signed and unsigned integer expressions [-Wsign-compare] >>>> if (write(fd,vals,m*n*sizeof(double)) != ((unsigned int) >>>> (m*n))*sizeof(double)) abort(); >>>> ^ >>>> /sandbox/petsc/petsc.clone-3/src/mat/examples/tests/ex45.c: In function >>>> ‘void Store1DArray(int, double*, const char*, int*)’: >>>> /sandbox/petsc/petsc.clone-3/src/mat/examples/tests/ex45.c:97:36: warning: >>>> comparison between signed and unsigned integer expressions [-Wsign-compare] >>>> if (write(fd,a,m*sizeof(double)) != ((unsigned int)m)*sizeof(double)) >>>> abort(); >>>> >>>> >>>> It can be found here >>>> ftp://ftp.mcs.anl.gov/pub/petsc/nightlylogs/archive/2016/09/13/examples_next_arch-linux-opt-cxx-quad_grind.log >>> >
