don't have access to (e.g., fprintf, which needs the library type
FILE), fail with a warning and forget about the builtin
entirely. Previously, we would actually provide an error, which breaks
autoconf's super-lame checks for fprintf, longjmp, etc. Fixes PR8316.
llvm-svn: 122744
- This is designed to make it obvious that %clang_cc1 is a "test variable"
which is substituted. It is '%clang_cc1' instead of '%clang -cc1' because it
can be useful to redefine what gets run as 'clang -cc1' (for example, to set
a default target).
llvm-svn: 91446
library function, accept this declaration and pretend that we do not
know that this is a library function. autoconf depends on this
(broken) behavior.
llvm-svn: 67541
functions, so if we're declaring a static we should implicitly declare
a library function by the same name (e.g., malloc, strdup). Fixes PR3592.
llvm-svn: 64736
- If a declaration is an invalid redeclaration of an existing name,
complain about the invalid redeclaration then avoid adding it to
the AST (we can still parse the definition or initializer, if any).
- If the declaration is invalid but there is no prior declaration
with that name, introduce the invalid declaration into the AST
(for later error recovery).
- If the declaration is an invalid redeclaration of a builtin that
starts with __builtin_, we produce an error and drop the
redeclaration. If it is an invalid redeclaration of a library
builtin (e.g., malloc, printf), warn (don't error!) and drop the
redeclaration.
If a user attempts to define a builtin, produce an error and (if it's
a library builtin like malloc) suggest -ffreestanding.
This addresses <rdar://problem/6097585> and PR2892. However, PR3588 is
still going to cause some problems when builtins are redeclared
without a prototype.
llvm-svn: 64639
we can define builtins such as fprintf, vfprintf, and
__builtin___fprintf_chk. Give a nice error message when we need to
implicitly declare a function like fprintf.
llvm-svn: 64526
etc.) when we perform name lookup on them. This ensures that we
produce the correct signature for these functions, which has two
practical impacts:
1) When we're supporting the "implicit function declaration" feature
of C99, these functions will be implicitly declared with the right
signature rather than as a function returning "int" with no
prototype. See PR3541 for the reason why this is important (hint:
GCC always predeclares these functions).
2) If users attempt to redeclare one of these library functions with
an incompatible signature, we produce a hard error.
This patch does a little bit of work to give reasonable error
messages. For example, when we hit case #1 we complain that we're
implicitly declaring this function with a specific signature, and then
we give a note that asks the user to include the appropriate header
(e.g., "please include <stdlib.h> or explicitly declare 'malloc'"). In
case #2, we show the type of the implicit builtin that was incorrectly
declared, so the user can see the problem. We could do better here:
for example, when displaying this latter error message we say
something like:
'strcpy' was implicitly declared here with type 'char *(char *, char
const *)'
but we should really print out a fake code line showing the
declaration, like this:
'strcpy' was implicitly declared here as:
char *strcpy(char *, char const *)
This would also be good for printing built-in candidates with C++
operator overloading.
The set of C library functions supported by this patch includes all
functions from the C99 specification's <stdlib.h> and <string.h> that
(a) are predefined by GCC and (b) have signatures that could cause
codegen issues if they are treated as functions with no prototype
returning and int. Future work could extend this set of functions to
other C library functions that we know about.
llvm-svn: 64504