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Date: Mon, 19 Nov 2007 04:57:00 -0000
Subject: [Bug c/34146]  New: [4.1/4.2/4.3 Regression] Inefficient code with compound literals inside a CONSTRUCTO
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Exactly like PR 33723 except the compound literal is inside a CONSTRUCTOR (you
can combine compound literals and normal constructors to make this worse).
Testcase:
typedef  struct
  {
    int f1, f2, f3, f4, f5, f6, f7, f8;
    long int f9, f10;
    int f11;
  } f;
typedef union
{
  f f;
  char s[56];
  long int a;
} T;

void
foo (void)
{
  T t =  { { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 } };
  test (&t);
}

void
bar (void)
{
  T t = { (f){ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 } };
  test (&t);
}

----
Basically the fix for PR 33723 was not complete.  I have a more complete fix
but it does not fix the case where you include more compound literals inside
another one.


-- 
           Summary: [4.1/4.2/4.3 Regression] Inefficient code with compound
                    literals inside a CONSTRUCTO
           Product: gcc
           Version: 4.3.0
            Status: UNCONFIRMED
          Keywords: missed-optimization
          Severity: normal
          Priority: P3
         Component: c
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: pinskia at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34146