RFA: GCC stabs don't contain prototype info

[Jim Blandy]

This comes as a bit of a surprise to me, but it seems that stabs
generated by GCC don't indicate whether a given function was defined
with a prototype or not.  The argument types should appear after the
return types, each preceded by a semicolon, but for the following
input program:

        int foo (int a, float b) { return a + b; }

`gcc -save-temps -O2 -g -c' generates the following relevant stabs:

    .stabs "int:t(0,1)=r(0,1);0020000000000;0017777777777;",128,0,0,0
    .stabs "float:t(0,12)=r(0,1);4;0;",128,0,0,0
    .stabs "foo:F(0,1)",36,0,1,foo
    .stabs "a:P(0,1)",64,0,1,8
    .stabs "b:P(0,12)",64,0,1,9
    .stabs "",36,0,0,.LLscope0-foo
            .stabs "",100,0,0,.Letext

There is no no prototype info here.  There's no way for GDB to know
that the function expects its second argument to be passed as a float,
not promoted to a double, as the K&R-style rules specify.

Thus:

2001-11-26  Jim Blandy  <jimb@redhat.com>

	* gdb.base/callfuncs.exp: The stabs generated by GCC don't tell us
	whether functions are prototyped or not, so we can't possibly pass
	arguments to t_float_values2 properly.

Index: gdb/testsuite/gdb.base/callfuncs.exp
===================================================================
RCS file: /cvs/cvsfiles/devo/gdb/testsuite/gdb.base/callfuncs.exp,v
retrieving revision 1.46
diff -c -r1.46 callfuncs.exp
*** gdb/testsuite/gdb.base/callfuncs.exp	2001/11/10 00:08:23	1.46
--- gdb/testsuite/gdb.base/callfuncs.exp	2001/11/27 03:24:59
***************
*** 142,147 ****
--- 142,150 ----
  	gdb_test "p t_float_values(float_val1,-2.3765)" " = 1"
  
  	# Test passing of arguments which might not be widened.
+         # Under stabs, GCC doesn't tell us whether the function was
+         # prototyped or not.
+         if {$gcc_compiled} { setup_xfail_format "stabs" }
  	gdb_test "p t_float_values2(0.0,0.0)" " = 0"
  
  	# Although PR 5318 mentions SunOS specifically, this seems
***************
*** 152,158 ****
--- 155,166 ----
  		setup_xfail "alpha-dec-osf2*" "i*86-*-sysv4*" 5318
  	    }
  	}
+         
+         # Under stabs, GCC doesn't tell us whether the function was
+         # prototyped or not.
+         if {$gcc_compiled} { setup_xfail_format "stabs" }
  	gdb_test "p t_float_values2(3.14159,float_val2)" " = 1"
+ 
  	gdb_test "p t_small_values(1,2,3,4,5,6,7,8,9,10)" " = 55"
  
  	gdb_test "p t_double_values(0.0,0.0)" " = 0"
***************
*** 289,294 ****
--- 297,304 ----
  	}
      }
  }
+ 
+ get_debug_format
  
  # Make sure that malloc gets called and that the floating point unit
  # is initialized via a call to t_double_values.