[cfe-dev] Question about clang-format

[Graham St Jack via cfe-dev]

Hi all,

I am looking at using clang-format, and like everyone else with a 
pre-existing quirky style, there are some things that clang-format 
doesn't seem to handle for me.

Most of the issues are minor - we can just redefine our style, or they 
occur rarely enough for it not to matter.

Some things that stand out as odd though (and make adoption difficult) 
are the following blocks of code formatted with this .clang-format file, 
using clang-format-3.8 built from trunk source yesterday.

BasedOnStyle: LLVM

AlignConsecutiveAssignments:                    true
AlignConsecutiveDeclarations:                   true
AllowShortCaseLabelsOnASingleLine:              true
AllowShortFunctionsOnASingleLine:               Inline
BinPackParameters:                              false
BinPackArguments:                               false
BraceWrapping:
   IndentBraces:          false
   AfterNamespace:        false
   AfterClass:            true
   AfterControlStatement: true
   AfterEnum:             true
   AfterFunction:         true
   AfterStruct:           true
   AfterUnion:            true
   BeforeCatch:           true
   BeforeElse:            true
BreakBeforeBraces:                              Custom
ConstructorInitializerIndentWidth:              2
ContinuationIndentWidth:                        2
ConstructorInitializerAllOnOneLineOrOnePerLine: true
MaxEmptyLinesToKeep:                            1

----------------------------------------

   int *    err       = 0;
   ino_t_xx dir_inode = 0;
   gen_t    dir_gen   = 0;

Here, the variables and equal-signs are lined up beautifully, but the 
star isn't hard up against 'err' - which I would have expected given the 
fact that LLVM sets PointerAlignment to Right. Looking into the 
implementation (and doing some experiments), it looks like 'Right' just 
means "no need to put a space to the right of a star" - but plenty of 
spaces can be inserted to align the variable. Is this intentional, and 
if so, is there a plan to add a new option to align pointers/references 
to the right (as distinct from not-left like now)?

Since (regrettably) in C/C++, "pointerness" is associated with the 
variable and not the type, having the star hard up against the variable 
seems to me to be something that a lot of people would want.


----------------------------------------

  static int find_highest_index(ino_t base_inode,
                               gen_t     base_gen,
                               int       fd,
                               uint32_t *highest_index)

This looks like a bug - if it aligns some of the parameters, it should 
align all of them.

----------------------------------------

static int find_highest_index(
   ino_t base_inode, gen_t base_gen, int fd, uint32_t *highest_index, 
bool dummy)

This looks like a bug too - I added an extra parameter with a short type 
to demonstrate that the first and last parameters aren't aligned, but it 
put them all on one line. If there is an extra configuration parameter 
that would prevent this, please let me know.

----------------------------------------

static int find_highest_index(ino_t base_inode,
                               int       fd,
                               uint32_t *highest_index,
                               bool dummy)

Here is the example that shows the first and last parameter aren't 
aligned, but the others are.


Thanks

-- 
Graham St Jack | Software Engineer | Quantum