Commit Graph

9 Commits

Author SHA1 Message Date
Bill Wendling 91b3823bd0 [clang][Sema] Use size of char in bits for void types
The extension that allows for pointer arithmetic on 'void' types treats
the 'void' as a 'char'. We should use the 'char' size in bits instead of
1 (the number of bytes) to allow warning when pointer arithmetic would
go out of bounds.

Differential Revision: https://reviews.llvm.org/D135989
2022-10-14 14:46:19 -07:00
serge-sans-paille f764dc99b3 [clang] Introduce -fstrict-flex-arrays=<n> for stricter handling of flexible arrays
Some code [0] consider that trailing arrays are flexible, whatever their size.
Support for these legacy code has been introduced in
f8f6324983 but it prevents evaluation of
__builtin_object_size and __builtin_dynamic_object_size in some legit cases.

Introduce -fstrict-flex-arrays=<n> to have stricter conformance when it is
desirable.

n = 0: current behavior, any trailing array member is a flexible array. The default.
n = 1: any trailing array member of undefined, 0 or 1 size is a flexible array member
n = 2: any trailing array member of undefined or 0 size is a flexible array member

This takes into account two specificities of clang: array bounds as macro id
disqualify FAM, as well as non standard layout.

Similar patch for gcc discuss here: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101836

[0] https://docs.freebsd.org/en/books/developers-handbook/sockets/#sockets-essential-functions
2022-07-18 12:45:52 +02:00
Vitaly Buka cdfa15da94 Revert "[clang] Introduce -fstrict-flex-arrays=<n> for stricter handling of flexible arrays"
This reverts D126864 and related fixes.

This reverts commit 572b08790a.
This reverts commit 886715af96.
2022-06-27 14:03:09 -07:00
serge-sans-paille 886715af96 [clang] Introduce -fstrict-flex-arrays=<n> for stricter handling of flexible arrays
Some code [0] consider that trailing arrays are flexible, whatever their size.
Support for these legacy code has been introduced in
f8f6324983 but it prevents evaluation of
__builtin_object_size and __builtin_dynamic_object_size in some legit cases.

Introduce -fstrict-flex-arrays=<n> to have stricter conformance when it is
desirable.

n = 0: current behavior, any trailing array member is a flexible array. The default.
n = 1: any trailing array member of undefined, 0 or 1 size is a flexible array member
n = 2: any trailing array member of undefined or 0 size is a flexible array member
n = 3: any trailing array member of undefined size is a flexible array member (strict c99 conformance)

Similar patch for gcc discuss here: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101836

[0] https://docs.freebsd.org/en/books/developers-handbook/sockets/#sockets-essential-functions
2022-06-24 16:13:29 +02:00
Aaron Ballman e765e0bc8e Use functions with prototypes when appropriate; NFC
A significant number of our tests in C accidentally use functions
without prototypes. This patch converts the function signatures to have
a prototype for the situations where the test is not specific to K&R C
declarations. e.g.,

  void func();

becomes

  void func(void);

This is the first batch of tests being updated (there are a significant
number of other tests left to be updated).
2022-02-03 16:42:27 -05:00
Nick Desaulniers 3a604fdbcd [Clang][CFG] check children statements of asm goto
When performing CFG based analyses, don't forget to check the child
statements of an asm goto, such as the expressions used for
inputs+outputs.

Fixes: https://github.com/llvm/llvm-project/issues/51024
Fixes: https://github.com/ClangBuiltLinux/linux/issues/1439

Reviewed By: void, jyknight, jyu2, efriedma

Differential Revision: https://reviews.llvm.org/D116059
2022-01-07 14:11:08 -08:00
Ted Kremenek 7ebb493375 Teach IsTailPaddedMemberArray() (used by -Warray-bounds) that a FieldDecl may have a Typedef type, and not always a ConstantArrayType.
Fixes <rdar://problem/11387038>.

llvm-svn: 156464
2012-05-09 05:35:08 +00:00
Richard Smith 13f6718b42 PR11594: Don't blindly build a UnaryOperator UO_Minus on an expression which
might not be an rvalue when checking array accesses. Instead, pass through a
flag indicating the array index is negated.

llvm-svn: 146753
2011-12-16 19:31:14 +00:00
Kaelyn Uhrain 0fb0bb179a Add a test case for the divide-by-zero fix in r137234
llvm-svn: 137240
2011-08-10 19:47:25 +00:00