nvcc optimization flags (--optimize)

Accelerated Computing CUDA CUDA Programming and Performance
1

Hi,

according to the nvcc man-page, there is a optimization flag (–optimize or -O). My code compiles fine if I don’t use any optimization flags, or set them to --optimize 0. However, when I try to use the optimizer flags (–optimize 2), I get compile errors such as these below:

/usr/include/string.h:43: error: inline function ‘void* memcpy(void*, const void*, size_t)’ cannot be declared weak
/usr/include/bits/string3.h:49: error: inline function ‘void* memcpy(void*, const void*, size_t)’ cannot be declared weak
/usr/local/cuda/bin/…/include/math_functions.h:422: error: inline function ‘int __signbit(double)’ cannot be declared weak
/usr/include/bits/mathcalls.h:350: error: inline function ‘int __signbit(double)’ cannot be declared weak

My complete nvcc command looks as follows: nvcc -c -arch sm_13 --ptxas-options=-v -m64 --optimize 2

Any ideas what is causing these compilation errors, and how to get around them (while still using nvcc optimization)? Any help is greatly appreciated!

Thanks,

Michael

2

Hi,

These errors can appear when using gcc 4.4+
Adding the following option can help: --compiler-options -fno-inline

Jeremie.

3

Hi,

These errors can appear when using gcc 4.4+
Adding the following option can help: --compiler-options -fno-inline

Jeremie.

4

Thanks for your suggestions.

I’m using gcc-4.3 (i.e. < gcc-4.4). I also tried the suggested flags. They reduced the number of errors from

/usr/include/string.h:43: error: inline function ‘void* memcpy(void*, const void*, size_t)’ cannot be declared weak
/usr/include/string.h:64: error: inline function ‘void* memset(void*, int, size_t)’ cannot be declared weak
/usr/include/bits/string3.h:49: error: inline function ‘void* memcpy(void*, const void*, size_t)’ cannot be declared weak
/usr/include/bits/string3.h:78: error: inline function ‘void* memset(void*, int, size_t)’ cannot be declared weak
/usr/local/cuda/bin/…/include/common_functions.h:59: error: inline function ‘void* memset(void*, int, size_t)’ cannot be declared weak
/usr/local/cuda/bin/…/include/common_functions.h:62: error: inline function ‘void* memcpy(void*, const void*, size_t)’ cannot be declared weak
/usr/local/cuda/bin/…/include/math_functions.h:422: error: inline function ‘int __signbit(double)’ cannot be declared weak
/usr/local/cuda/bin/…/include/math_functions.h:427: error: inline function ‘int __signbitf(float)’ cannot be declared weak
/usr/local/cuda/bin/…/include/math_functions.h:440: error: inline function ‘int __signbitl(long double)’ cannot be declared weak
/usr/include/bits/mathcalls.h:350: error: inline function ‘int __signbit(double)’ cannot be declared weak
/usr/include/bits/mathcalls.h:350: error: inline function ‘int __signbitf(float)’ cannot be declared weak
/usr/include/bits/mathcalls.h:350: error: inline function ‘int __signbitl(long double)’ cannot be declared weak
/usr/include/bits/mathinline.h:38: error: inline function ‘int __signbitf(float)’ cannot be declared weak
/usr/include/bits/mathinline.h:50: error: inline function ‘int __signbit(double)’ cannot be declared weak
/usr/include/bits/mathinline.h:62: error: inline function ‘int __signbitl(long double)’ cannot be declared weak

to

/usr/include/string.h:43: error: inline function ‘void* memcpy(void*, const void*, size_t)’ cannot be declared weak
/usr/include/string.h:64: error: inline function ‘void* memset(void*, int, size_t)’ cannot be declared weak
/usr/include/bits/string3.h:49: error: inline function ‘void* memcpy(void*, const void*, size_t)’ cannot be declared weak
/usr/include/bits/string3.h:78: error: inline function ‘void* memset(void*, int, size_t)’ cannot be declared weak
/usr/local/cuda/bin/…/include/common_functions.h:59: error: inline function ‘void* memset(void*, int, size_t)’ cannot be declared weak
/usr/local/cuda/bin/…/include/common_functions.h:62: error: inline function ‘void* memcpy(void*, const void*, size_t)’ cannot be declared weak

Any ideas how I can get rid of these?? I don’t use memcpy or memset in my device code, and I also don’t use them in my .cu and .cuh files.

Thanks for any hints!

5

Thanks for your suggestions.

I’m using gcc-4.3 (i.e. < gcc-4.4). I also tried the suggested flags. They reduced the number of errors from

/usr/include/string.h:43: error: inline function ‘void* memcpy(void*, const void*, size_t)’ cannot be declared weak
/usr/include/string.h:64: error: inline function ‘void* memset(void*, int, size_t)’ cannot be declared weak
/usr/include/bits/string3.h:49: error: inline function ‘void* memcpy(void*, const void*, size_t)’ cannot be declared weak
/usr/include/bits/string3.h:78: error: inline function ‘void* memset(void*, int, size_t)’ cannot be declared weak
/usr/local/cuda/bin/…/include/common_functions.h:59: error: inline function ‘void* memset(void*, int, size_t)’ cannot be declared weak
/usr/local/cuda/bin/…/include/common_functions.h:62: error: inline function ‘void* memcpy(void*, const void*, size_t)’ cannot be declared weak
/usr/local/cuda/bin/…/include/math_functions.h:422: error: inline function ‘int __signbit(double)’ cannot be declared weak
/usr/local/cuda/bin/…/include/math_functions.h:427: error: inline function ‘int __signbitf(float)’ cannot be declared weak
/usr/local/cuda/bin/…/include/math_functions.h:440: error: inline function ‘int __signbitl(long double)’ cannot be declared weak
/usr/include/bits/mathcalls.h:350: error: inline function ‘int __signbit(double)’ cannot be declared weak
/usr/include/bits/mathcalls.h:350: error: inline function ‘int __signbitf(float)’ cannot be declared weak
/usr/include/bits/mathcalls.h:350: error: inline function ‘int __signbitl(long double)’ cannot be declared weak
/usr/include/bits/mathinline.h:38: error: inline function ‘int __signbitf(float)’ cannot be declared weak
/usr/include/bits/mathinline.h:50: error: inline function ‘int __signbit(double)’ cannot be declared weak
/usr/include/bits/mathinline.h:62: error: inline function ‘int __signbitl(long double)’ cannot be declared weak

to

/usr/include/string.h:43: error: inline function ‘void* memcpy(void*, const void*, size_t)’ cannot be declared weak
/usr/include/string.h:64: error: inline function ‘void* memset(void*, int, size_t)’ cannot be declared weak
/usr/include/bits/string3.h:49: error: inline function ‘void* memcpy(void*, const void*, size_t)’ cannot be declared weak
/usr/include/bits/string3.h:78: error: inline function ‘void* memset(void*, int, size_t)’ cannot be declared weak
/usr/local/cuda/bin/…/include/common_functions.h:59: error: inline function ‘void* memset(void*, int, size_t)’ cannot be declared weak
/usr/local/cuda/bin/…/include/common_functions.h:62: error: inline function ‘void* memcpy(void*, const void*, size_t)’ cannot be declared weak

Any ideas how I can get rid of these?? I don’t use memcpy or memset in my device code, and I also don’t use them in my .cu and .cuh files.

Thanks for any hints!