• Next Thread Prev Thread

• Posts   Search Threads

• wolfgang-svrcek-seiler July 10, 2009 3:57 AM PDT    Possible bug in inlined string functions of icc Version 11.1 (Build 20090511 Package ID: l_cproc_p_11.1.038) Hi all, When I compile the following program: #include <stdio.h> #include <string.h> int main() { char x[100]; int len; strcpy(x, "mumbo jumbo"); len = (int) strlen(x); printf("%dn", len); return 0; } with icc 11.1 and optimization level -O2 or higher, valgrind complains about numerous runtime errors, most probably initially triggered triggered inside strlen(). If, however, I compile it with '-nolib-inline', all error messages are gone. Besides, compiling with icc 10.1 or 11.0 also gives no errors. I hope that helps, greetings, Andreas Brandon Hewitt (Intel) July 10, 2009 4:20 PM PDT Rate   #1 Re: Possible bug in inlined string functions of icc Version 11.1 (Build 20090511 Package ID: l_cproc_p_11.1.038) Quoting - wolfgang-svrcek-seiler Hi all, When I compile the following program: #include <stdio.h> #include <string.h> int main() { char x[100]; int len; strcpy(x, "mumbo jumbo"); len = (int) strlen(x); printf("%dn", len); return 0; } with icc 11.1 and optimization level -O2 or higher, valgrind complains about numerous runtime errors, most probably initially triggered triggered inside strlen(). If, however, I compile it with '-nolib-inline', all error messages are gone. Besides, compiling with icc 10.1 or 11.0 also gives no errors. I hope that helps, greetings, Andreas I'll take a look at this.  What command line are you using for valgrind? Brandon Hewitt Intel Developer Support Tools Knowledge Base: http://software.intel.com/en-us/articles/tools Software Product support info: http://www.intel.com/software/support * Other names and brands may be claimed as the property of others. wolfgang-svrcek-seiler July 13, 2009 4:06 AM PDT Rate   #2 Reply To #1 Re: Possible bug in inlined string functions of icc Version 11.1 (Build 20090511 Package ID: l_cproc_p_11.1.038) Hi, thanks for the quick reply. The submitted example is a close to minimal test case. Command lines: icc tstr.c -g -O2 ... valgrind ./a.out | & less valgrind versio is 3.3.0, flags enabled by default are:  -v  --trace-children=yes --time-stamp=yes --error-limit=no --leak-check=full --leak-resolution=high best, Andreas Brandon Hewitt (Intel) August 21, 2009 11:21 AM PDT Rate   #3 Reply To #2 Re: Possible bug in inlined string functions of icc Version 11.1 (Build 20090511 Package ID: l_cproc_p_11.1.038) Quoting - wolfgang-svrcek-seiler Hi, thanks for the quick reply. The submitted example is a close to minimal test case. Command lines: icc tstr.c -g -O2 ... valgrind ./a.out | & less valgrind versio is 3.3.0, flags enabled by default are:  -v  --trace-children=yes --time-stamp=yes --error-limit=no --leak-check=full --leak-resolution=high best, Andreas Looks like this is a known limitation of valgrind.  See http://valgrind.org/docs/manual/dist.news.html under Known Limitations: - Memcheck is unusable with the Intel compiler suite version 11.1, when it generates code for SSE2-and-above capable targets. This is because of icc's use of highly optimised inlined strlen implementations. It causes Memcheck to report huge numbers of false errors even in simple programs. Helgrind and DRD may also have problems. If you're using the compiler for 32-bit, you can use the -mia32 option to workaround this, but this option will likely impact your performance. Brandon Hewitt Intel Developer Support Tools Knowledge Base: http://software.intel.com/en-us/articles/tools Software Product support info: http://www.intel.com/software/support * Other names and brands may be claimed as the property of others.

• = Best Answer

  Next Thread Prev Thread

Intel Software Network Forums Statistics

16,376 users have contributed to 46,361 threads and 164,026 posts to date.

For more complete information about compiler optimizations, see our Optimization Notice.