Error: unable to inject with 1.11.0

System: CentOS 7 x86_64
gcc version: 4.8.5
drmemory version: I downloaded form the github named "DrMemory-Linux-1.11.0-2.tar.gz"
1. My test code like:
`#include `
`using namespace std;`
`int main()`
`{`
` char *a = new char[10]();`
` cout << "Hello world" << endl;`
` return 0;`
`}`

2. then `g++ -m32 -g -fno-inline -fno-omit-frame-pointer *.cpp -o myapp`,make sure it can run successfully.
3. when I used the command `./drmemory -- ./myapp` in the directory `~/Desktop/DrMemory-Linux-1.11.0-2/bin/`, it returned "ERROR: unable to inject"

Please tell me how to solve the problem, and thank you very much.