[Bug c++/17411] New: 4.0: ICE in immed_double_const

["gcc-bugzilla at gcc dot gnu dot org" <gcc-bugzilla at gcc dot gnu dot org>]

g++ crashes on the code below when -O1 is used:

$ ./cc1plus -O1 -quiet x.cc
x.cc: In function `void foo()':
x.cc:10: internal compiler error: in immed_double_const, at emit-rtl.c:464
Please submit a full bug report,
with preprocessed source if appropriate.
See <URL:http://gcc.gnu.org/bugs.html> for instructions.
$


It's dying at this assertion in immed_double_const:

      gcc_assert (GET_MODE_CLASS (mode) == MODE_INT
		  || GET_MODE_CLASS (mode) == MODE_PARTIAL_INT
		  /* We can get a 0 for an error mark.  */
		  || GET_MODE_CLASS (mode) == MODE_VECTOR_INT
		  || GET_MODE_CLASS (mode) == MODE_VECTOR_FLOAT);

Here, mode is SFmode.


If i go up to the caller, expand_expr_real_1, here is the tree being expanded:

 <integer_cst 0x400d3e40 type <real_type 0x40029bc8 float> constant invariant 0>

Environment:
System: Linux karma 2.6.7 #18 Wed Jul 14 03:27:01 EDT 2004 i686 i686 i386 GNU/Linux
Architecture: i686

	<machine, os, target, libraries (multiple lines)>
host: i686-pc-linux-gnu
build: i686-pc-linux-gnu
target: i686-pc-linux-gnu
configured with: /home/sss/gcc/gcc/configure --prefix=/usr/local/gcc --enable-threads=posix --enable-long-long --enable-languages=c,c++,f95

How-To-Repeat:

Compile with -O1:

---------------------------------------
struct CalibData {
  float mean_pedestal;
};

struct pair
{
  CalibData second;
  pair(const CalibData& __b) : second(__b) { }
};

void insert(const pair& __x);

void foo()
{
  insert(pair(CalibData()));
}
---------------------------------------
------- Additional Comments From snyder at fnal dot gov  2004-09-10 21:14 -------
Fix:
	<how to correct or work around the problem, if known (multiple lines)>

-- 
           Summary: 4.0: ICE in immed_double_const
           Product: gcc
           Version: 3.5.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: snyder at fnal dot gov
                CC: gcc-bugs at gcc dot gnu dot org
 GCC build triplet: i686-pc-linux-gnu
  GCC host triplet: i686-pc-linux-gnu
GCC target triplet: i686-pc-linux-gnu


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17411