Where are my compiler warnings?

[gfunk]

Weird. I compiled the code on gcc version 3.2.3 20030502 (Red Hat Linux 3.2.3-20) and got:

test.cc: In function `int main(int, char**)':
test.cc:3: warning: `const char*ptr' might be used uninitialized in this
function
test.cc:4: warning: `char*ptr2' might be used uninitialized in this function

Don't have your version installed though, so it may be release-specific. However, my guess is that the compiler has optimized out the const char* ptr reference, and thus does not report it.

[drhex]

I've tried to check what the "const ptr" points to when no codeline assigns a value to it. It seems to point to the "hello" string anyway. Does g++ assign uninitialized "const char *"s to the first string in the data section or something?
I guess I'd better file a bug-report.

[gfunk]

Try compiling without the -O2 (which performs level 2 optimizations). It sounds like the code is just being optimized out.

[drhex]

According to the g++ man page, optimization is required for the compiler to be able to notice uninitialized variables.
I tried compiling with -O1 and without any -O, in neither case do I get a warning about "ptr may be used initialized".

[drhex]

There seems to be a lively discussion about how to handle uninitialized variables: http://gcc.gnu.org/wiki/Better_Uninitialized_Warnings