[Bug c++/27312] New: excessive stack use for automatic object on stack

[avi at argo dot co dot il]

compiling the following

------start-code--------
struct X {
    void g();
};

void g();

void f()
{
    X x;

    x.g();
    g();
}
------end-code---------

yields (with -O2)

     subl    $24, %esp

in the prologue. without the empty class only 12 bytes are subtracted,
presumably to preserve stack alignment.

this is wasteful of stack space.


-- 
           Summary: excessive stack use for automatic object on stack
           Product: gcc
           Version: 4.1.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: avi at argo dot co dot il
 GCC build triplet: x86_64-redhat-linux
  GCC host triplet: x86_64-redhat-linux
GCC target triplet: i386-redhat-linux (with -m32)


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=27312