[cfe-dev] clang::CompoundLiteral::getInitializer() should use cast_or_null() (or I am missing something)

[Paolo Bolzoni]

On Tue, 16 Dec 2008 22:59:21 -0800
Chris Lattner <clattner at apple.com> wrote:
> hi Paolo,
> 
> Please include an example, it would be very useful to understand the  
> details of what you're talking about,
> 
> -Chris


I attached an extract of the file that gives me problems.

It is a function from gcc.c downloadable from 
http://people.csail.mit.edu/smcc/projects/single-file-programs/

I just added some meaningless definitions of structures and variables so
the file does compile with:
$ gcc -c -std=gnu89 -w

This instead is an extract of clang driver ast dump:
'''
(BinaryOperator 0x18c4cc0 <col:14, col:67> 'unsigned long' '+'
  (ImplicitCastExpr 0x18c4c80 <col:14, col:16> 'unsigned long'
    (ParenExpr 0x18c4ac0 <col:14, col:16> 'size_t':'unsigned int'
      (DeclRefExpr 0x18c4a80 <col:15> 'size_t':'unsigned int' Var='s'
0x18c4700))) (ParenExpr 0x18c4c40 <col:20, col:67> 'unsigned long'
    (ParenExpr 0x18c4c00 <col:21, col:66> 'unsigned long'
      (UnaryOperator 0x18c4bc0 <col:22, col:64> 'unsigned long' prefix
'__builtin_offsetof' (MemberExpr 0x18c4b80 <:0:0, gcc_extract.c:61:64>
'int' .u 0x18b1bd0 (CompoundLiteralExpr 0x18c4b00 <:0:0> 'struct
max_alignment' <<<NULL>>>))))))
'''

I think the <<<NULL>>> in compound literal expression is problem.
this little member function of a statement visitor crashes:
'''
void Visitor::VisitCompoundLiteralExpr(clang::CompoundLiteralExpr *node) {
    std::cout << "CompoundLiteral\n";
//  if (node-> hasInitializer()) {
       std::cout << "hasInitializer\n";
       clang::Expr* init = node-> getInitializer();
       Visit(init);
//  }
//  else {
//    std::cout << "no initializer\n";
//  }
}
'''
The commented part is a test of mine, I tried adding a member to
clang::CompoundLiteralExpr:

bool hasInitializer() const { return Init != 0; }

and with this slight modification it seems working fine.


Re-reading better it does not seem ext_gnu_empty_initializer related, it
seem more __builtin_offsetof related, sorry for the confusion.

Thanks,
pb
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