Extended Description

Code motion is noticed when running tests with and without the debug info at O2.
I've triaged this bug, and it's not a duplicate of BZ #​18590.

========Testcase==================
extern void foo(char *dst,unsigned siz,const char *src);
extern const char * i2str(int);

struct AAA3 {
AAA3(const char *value) { foo(text,sizeof(text),value);}
void operator=(const char value) { foo(text,sizeof(text),value);}
operator const char() const { return text;}
char text[4];
};

void bar (int param1,int param2) {
const char * temp(0);

if (param2) {
temp = i2str(param2);
}
AAA3 var1("");
AAA3 var2("");

if (param1)
var2 = "+";
else
var2 = "-";
var1 = "";
}

clang -c -g -O2 test.cpp -o test.g.o
clang -c -O2 test.cpp -o test.o

objdump -d test.g.o > test.g.txt
objdump -d test.o > test.txt

diff test.txt test.g.txt
2c2
< test.o: file format elf64-x86-64

test.g.o: file format elf64-x86-64
23,25c23,25
< 39: 48 8d 3c 24 lea (%rsp),%rdi
< 3d: be 04 00 00 00 mov $0x4,%esi
< 42: 85 db test %ebx,%ebx

39: 85 db test %ebx,%ebx
3b: 48 8d 3c 24 lea (%rsp),%rdi
3f: be 04 00 00 00 mov $0x4,%esi

Katya.