replica
/
hanchenye-llvm-project
2
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

add support for initializing static vars with a cast to union (gcc extension) 

llvm-svn: 62261
This commit is contained in:
Nuno Lopes 2009-01-15 16:44:45 +00:00
parent 4bdf021e05
commit 6be2939d5d
2 changed files with 18 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
clang/lib/Sema/SemaDecl.cpp
View File

@ -2228,7 +2228,14 @@ bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) {
// Allow block exprs at top level.
if (Init->getType()->isBlockPointerType())
return false;
// GCC cast to union extension
// note: the validity of the cast expr is checked by CheckCastTypes()
if (CastExpr *C = dyn_cast<CastExpr>(Init)) {
QualType T = C->getType();
return T->isUnionType() && CheckForConstantInitializer(C->getSubExpr(), T);
}
InitializerElementNotConstant(Init);
return true;
}

10
clang/test/Sema/cast-to-union.c
View File

@ -7,3 +7,13 @@ void test(int x) {
f((union u)x); // expected-warning {{C99 forbids casts to union type}}
f((union u)&x); // expected-error {{cast to union type from type 'int *' not present in union}}
}
union u w = (union u)2; // expected-warning {{C99 forbids casts to union type}}
union u ww = (union u)1.0; // expected-error{{cast to union type from type 'double' not present in union}}
union u x = 7; // expected-error{{incompatible type initializing 'int', expected 'union u'}}
int i;
union u zz = (union u)i; // expected-error{{initializer element is not a compile-time constant}} expected-warning {{C99 forbids casts to union type}}
struct s {int a, b;};
struct s y = { 1, 5 };
struct s z = (struct s){ 1, 5 };