Re: Git compile warnings (under mac/clang)

2015-01-23 Thread Junio C Hamano
Jeff King p...@peff.net writes:

 diff --git a/fsck.c b/fsck.c
 index 15cb8bd..8f8c82f 100644
 --- a/fsck.c
 +++ b/fsck.c
 @@ -107,7 +107,7 @@ static int fsck_msg_severity(enum fsck_msg_id msg_id,
  {
  int severity;
  
 -if (options-msg_severity  msg_id = 0  msg_id  FSCK_MSG_MAX)
 +if (options-msg_severity  ((unsigned int) msg_id)  FSCK_MSG_MAX)
  severity = options-msg_severity[msg_id];
  else {
  severity = msg_id_info[msg_id].severity;
 -- snap --
 
 What do you think? Michael, does this cause more Clang warnings,
 or would it resolve the issue?

 Hmm, yeah, that does not seem unreasonable, and is more localized.

Or we could force enum to be signed by defining FSCK_MSG_UNUSED to
be -1 at the very beginning of enum definition, without changing
anything else.  Then msg_id  0 would become a very valid
protection against programming mistakes, no?
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Re: Git compile warnings (under mac/clang)

2015-01-23 Thread Johannes Schindelin
Hi Peff,

On 2015-01-23 19:37, Jeff King wrote:
 On Fri, Jan 23, 2015 at 10:07:18AM -0800, Junio C Hamano wrote:
 
 [...] one thing that puzzles me is that the current code looks
 like:
 
   if (options-msg_severity  msg_id = 0  msg_id  FSCK_MSG_MAX)
 severity = options-msg_severity[msg_id];
   else {
 severity = msg_id_info[msg_id].severity;
 ...
   }
 
 So if the severity override list given by options exists, _and_ if we
 are in the enum range, then we use that. Otherwise, we dereference the
 global list. But wouldn't an out-of-range condition have the exact same
 problem dereferencing that global list?
 
 IOW, should this really be:
 
   if (msg_id  0 || msg_id = FSCK_MSG_MAX)
   die(BUG: broken enum);
 
   if (options-msg_severity)
   severity = options-msg_severity[msg_id];
   else
   severity = msg_id_info[msg_id].severity;
 
 ? And then you can spell that first part as assert(), which I suspect
 (but did not test) may shut up clang's warnings.

To be quite honest, I assumed that Git's source code was assert()-free. But I 
was wrong! So I'll go with that solution; it is by far the nicest one IMHO.

Thanks!
Dscho
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Re: Git compile warnings (under mac/clang)

2015-01-23 Thread Johannes Schindelin
Hi Peff,

On 2015-01-23 19:55, Jeff King wrote:
 On Fri, Jan 23, 2015 at 07:46:36PM +0100, Johannes Schindelin wrote:
 
  ? And then you can spell that first part as assert(), which I suspect
  (but did not test) may shut up clang's warnings.

 To be quite honest, I assumed that Git's source code was
 assert()-free. But I was wrong! So I'll go with that solution; it is
 by far the nicest one IMHO.
 
 OK, here it is as a patch on top of js/fsck-opt. Please feel free to
 squash rather than leaving it separate.
 
 I tested with clang-3.6, and it seems to make the warning go away.
 
 -- 8 --
 Subject: [PATCH] fsck_msg_severity: range-check enum with assert()
 
 An enum is passed into the function, which we use to index a
 fixed-size array. We double-check that the enum is within
 range as a defensive measure. However, there are two
 problems with this:
 
   1. If it's not in range, we then use it to index another
  array of the same size. Which will have the same problem.
  We should probably die instead, as this condition
  should not ever happen.
 
   2. The bottom end of our range check is tautological
  according to clang, which generates a warning. Clang is
  not _wrong_, but the point is that we are trying to be
  defensive against something that should never happen
  (i.e., somebody abusing the enum).
 
 We can solve both by switching to a separate assert().
 
 Signed-off-by: Jeff King p...@peff.net
 ---
  fsck.c | 4 +++-
  1 file changed, 3 insertions(+), 1 deletion(-)
 
 diff --git a/fsck.c b/fsck.c
 index 15cb8bd..53c0849 100644
 --- a/fsck.c
 +++ b/fsck.c
 @@ -107,7 +107,9 @@ static int fsck_msg_severity(enum fsck_msg_id msg_id,
  {
   int severity;
  
 - if (options-msg_severity  msg_id = 0  msg_id  FSCK_MSG_MAX)
 + assert(msg_id = 0  msg_id  FSCK_MSG_MAX);
 +
 + if (options-msg_severity)
   severity = options-msg_severity[msg_id];
   else {
   severity = msg_id_info[msg_id].severity;

I also ended up with that solution!

Thanks!
Dscho
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Re: Git compile warnings (under mac/clang)

2015-01-23 Thread Jeff King
On Fri, Jan 23, 2015 at 10:07:18AM -0800, Junio C Hamano wrote:

  diff --git a/fsck.c b/fsck.c
  index 15cb8bd..8f8c82f 100644
  --- a/fsck.c
  +++ b/fsck.c
  @@ -107,7 +107,7 @@ static int fsck_msg_severity(enum fsck_msg_id msg_id,
   {
 int severity;
   
  -  if (options-msg_severity  msg_id = 0  msg_id  FSCK_MSG_MAX)
  +  if (options-msg_severity  ((unsigned int) msg_id)  FSCK_MSG_MAX)
 severity = options-msg_severity[msg_id];
 else {
 severity = msg_id_info[msg_id].severity;
  -- snap --
  
  What do you think? Michael, does this cause more Clang warnings,
  or would it resolve the issue?
 
  Hmm, yeah, that does not seem unreasonable, and is more localized.
 
 Or we could force enum to be signed by defining FSCK_MSG_UNUSED to
 be -1 at the very beginning of enum definition, without changing
 anything else.  Then msg_id  0 would become a very valid
 protection against programming mistakes, no?

Yeah, I think that would work, too. It is a little unfortunate in the
sense that it actually makes things _worse_ from the perspective of the
type system. That is, in the current code if you assume that everyone
else has followed the type rules, then an fsck_msg_id you get definitely
is indexable into various arrays. But if you add in a sentinel value,
now you (in theory) have to check for the sentinel value everywhere.

I'm not sure if that matters in practice, though, if you are going to be
defensive against people misusing the enum system in the first place
(e.g., you are worried about them passing a random int and having it
produce a segfault, you have to do range checks either way).

But of all the options outlined, I think I'd much rather just see an
assert() for something that should never happen, rather than mixing it
into the logic.

In that vein, one thing that puzzles me is that the current code looks
like:

  if (options-msg_severity  msg_id = 0  msg_id  FSCK_MSG_MAX)
  severity = options-msg_severity[msg_id];
  else {
  severity = msg_id_info[msg_id].severity;
  ...
  }

So if the severity override list given by options exists, _and_ if we
are in the enum range, then we use that. Otherwise, we dereference the
global list. But wouldn't an out-of-range condition have the exact same
problem dereferencing that global list?

IOW, should this really be:

  if (msg_id  0 || msg_id = FSCK_MSG_MAX)
die(BUG: broken enum);

  if (options-msg_severity)
severity = options-msg_severity[msg_id];
  else
severity = msg_id_info[msg_id].severity;

? And then you can spell that first part as assert(), which I suspect
(but did not test) may shut up clang's warnings.

-Peff
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Re: Git compile warnings (under mac/clang)

2015-01-23 Thread Junio C Hamano
Jeff King p...@peff.net writes:

 But of all the options outlined, I think I'd much rather just see an
 assert() for something that should never happen, rather than mixing it
 into the logic.

Surely.

 In that vein, one thing that puzzles me is that the current code looks
 like:

   if (options-msg_severity  msg_id = 0  msg_id  FSCK_MSG_MAX)
 severity = options-msg_severity[msg_id];
   else {
 severity = msg_id_info[msg_id].severity;
 ...
   }

 So if the severity override list given by options exists, _and_ if we
 are in the enum range, then we use that. Otherwise, we dereference the
 global list. But wouldn't an out-of-range condition have the exact same
 problem dereferencing that global list?

 IOW, should this really be:

   if (msg_id  0 || msg_id = FSCK_MSG_MAX)
   die(BUG: broken enum);

   if (options-msg_severity)
   severity = options-msg_severity[msg_id];
   else
   severity = msg_id_info[msg_id].severity;

 ? And then you can spell that first part as assert(), which I suspect
 (but did not test) may shut up clang's warnings.

Sounds like a sensible fix to me.
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Re: Git compile warnings (under mac/clang)

2015-01-23 Thread Jeff King
On Fri, Jan 23, 2015 at 07:46:36PM +0100, Johannes Schindelin wrote:

  ? And then you can spell that first part as assert(), which I suspect
  (but did not test) may shut up clang's warnings.
 
 To be quite honest, I assumed that Git's source code was
 assert()-free. But I was wrong! So I'll go with that solution; it is
 by far the nicest one IMHO.

OK, here it is as a patch on top of js/fsck-opt. Please feel free to
squash rather than leaving it separate.

I tested with clang-3.6, and it seems to make the warning go away.

-- 8 --
Subject: [PATCH] fsck_msg_severity: range-check enum with assert()

An enum is passed into the function, which we use to index a
fixed-size array. We double-check that the enum is within
range as a defensive measure. However, there are two
problems with this:

  1. If it's not in range, we then use it to index another
 array of the same size. Which will have the same problem.
 We should probably die instead, as this condition
 should not ever happen.

  2. The bottom end of our range check is tautological
 according to clang, which generates a warning. Clang is
 not _wrong_, but the point is that we are trying to be
 defensive against something that should never happen
 (i.e., somebody abusing the enum).

We can solve both by switching to a separate assert().

Signed-off-by: Jeff King p...@peff.net
---
 fsck.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/fsck.c b/fsck.c
index 15cb8bd..53c0849 100644
--- a/fsck.c
+++ b/fsck.c
@@ -107,7 +107,9 @@ static int fsck_msg_severity(enum fsck_msg_id msg_id,
 {
int severity;
 
-   if (options-msg_severity  msg_id = 0  msg_id  FSCK_MSG_MAX)
+   assert(msg_id = 0  msg_id  FSCK_MSG_MAX);
+
+   if (options-msg_severity)
severity = options-msg_severity[msg_id];
else {
severity = msg_id_info[msg_id].severity;
-- 
2.3.0.rc1.287.g761fd19

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Re: Git compile warnings (under mac/clang)

2015-01-23 Thread Jeff King
On Fri, Jan 23, 2015 at 12:48:29PM +0100, Johannes Schindelin wrote:

 This is what I have currently in the way of attempting to fix it (I
 still believe that Clang is wrong to make this a warning, and causes
 more trouble than it solves):

I agree. It is something we as the programmers cannot possibly know (the
compiler is free to decide which type however it likes) and its decision
does not impact the correctness of the code (the check is either useful
or tautological, and we cannot know which, so we are being warned about
being too careful!).

I guess you could argue that the standard defines enum-numbering to
start at 0, and increment by 1.  Therefore we should know that no valid
enum value is less than 0.  IOW, msg_id  0 being true must be the
result of a bug somewhere else in the program, where we assigned a value
outside of the enum range to the enum.

 Pointed out by Michael Blume. Jeff King provided the pointer to a commit
 fixing the same issue elsewhere in the Git source code.

It may be useful to reference the exact commit (3ce3ffb8) to help people
digging in the history (e.g., if we decide there is a better way to shut
up this warning and we need to find all the places to undo the
brain-damage).

 - for (i = 0; i  FSCK_MSG_MAX; i++) {
 + for (i = FSCK_MSG_MIN + 1; i  FSCK_MSG_MAX; i++) {

Ugh. It is really a shame how covering up this warning requires
polluting so many places. I don't think we have a better way, though,
aside from telling people to use -Wno-tautological-compare (and I can
believe that it _is_ a useful warning in some other circumstances, so it
seems a shame to lose it).

Unless we are willing to drop the = 0 check completely. I think it is
valid to do so regardless of the compiler's representation decision due
to the numbering rules I mentioned above. It kind-of serves as a
cross-check that we haven't cast some random int into the enum, but I
think we would do better to find those callsites (since they are not
guaranteed to work, anyway; in addition to signedness, it might choose a
much smaller representation).

I do not see either side of the bounds check here:

 + if (options-msg_severity 
 + msg_id  FSCK_MSG_MIN  msg_id  FSCK_MSG_MAX)

as really doing anything. Any code which triggers it must already cause
undefined behavior, I think (with the exception of msg_id == FSCK_MSG_MAX,
but presumably that is something we never expect to happen, either).

-Peff
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Re: Git compile warnings (under mac/clang)

2015-01-23 Thread Johannes Schindelin
Hi Peff,

On 2015-01-22 23:01, Jeff King wrote:
 On Thu, Jan 22, 2015 at 10:20:01PM +0100, Johannes Schindelin wrote:
 
 On 2015-01-22 20:59, Stefan Beller wrote:
  cc Johannes Schindelin johannes.schinde...@gmx.de who is working in
  the fsck at the moment
 
  On Thu, Jan 22, 2015 at 11:43 AM, Michael Blume blume.m...@gmail.com 
  wrote:
 
  CC fsck.o
  fsck.c:110:38: warning: comparison of unsigned enum expression = 0 is
  always true [-Wtautological-compare]
  if (options-msg_severity  msg_id = 0  msg_id  FSCK_MSG_MAX)
   ~~ ^  ~

 According to A2.5.4 of The C Programming Language 2nd edition:

 Identifiers declared as enumerators (see Par.A.8.4) are constants of 
 type int.

 Therefore, the warning is incorrect: any assumption about enum fsck_msg_id 
 to be unsigned is false.
 
 I'm not sure that made it to ANSI. C99 says (setion 6.7.2.2, paragraph
 4):
 
   Each enumerated type shall be compatible with char, a signed integer
   type, or an unsigned integer type. The choice of type is
   implementation-defined, but shall be capable of representing the
   values of all the members of the enumeration.
 
 I don't have a copy of C89, but this isn't mentioned in the (very
 cursory) list of changes found in C99. Anyway, that's academic.
 
 I think we dealt with a similar situation before, in
 3ce3ffb840a1dfa7fcbafa9309fab37478605d08.

Ww. That commit got a chuckle out of me...

This is what I have currently in the way of attempting to fix it (I still 
believe that Clang is wrong to make this a warning, and causes more trouble 
than it solves):

-- snipsnap --
commit 11b4c713f77081bf8342e5c02055ae8e18d28e8b
Author: Johannes Schindelin johannes.schinde...@gmx.de
Date:   Fri Jan 23 12:46:02 2015 +0100

fsck: fix clang -Wtautological-compare with unsigned enum

Clang warns that the fsck_msg_id enum is unsigned, missing that the
specification of the C language allows for C compilers interpreting
enums as signed.

To shut up Clang, we waste a full enum value just so that we compare
against an enum value without messing up the readability of the source
code.

Pointed out by Michael Blume. Jeff King provided the pointer to a commit
fixing the same issue elsewhere in the Git source code.

Signed-off-by: Johannes Schindelin johannes.schinde...@gmx.de

diff --git a/fsck.c b/fsck.c
index 15cb8bd..f76e7a9 100644
--- a/fsck.c
+++ b/fsck.c
@@ -65,6 +65,7 @@
 
 #define MSG_ID(id, severity) FSCK_MSG_##id,
 enum fsck_msg_id {
+   FSCK_MSG_MIN = 0,
FOREACH_MSG_ID(MSG_ID)
FSCK_MSG_MAX
 };
@@ -76,6 +77,7 @@ static struct {
const char *id_string;
int severity;
 } msg_id_info[FSCK_MSG_MAX + 1] = {
+   { NULL, -1 },
FOREACH_MSG_ID(MSG_ID)
{ NULL, -1 }
 };
@@ -85,7 +87,7 @@ static int parse_msg_id(const char *text, int len)
 {
int i, j;
 
-   for (i = 0; i  FSCK_MSG_MAX; i++) {
+   for (i = FSCK_MSG_MIN + 1; i  FSCK_MSG_MAX; i++) {
const char *key = msg_id_info[i].id_string;
/* id_string is upper-case, with underscores */
for (j = 0; j  len; j++) {
@@ -107,7 +109,8 @@ static int fsck_msg_severity(enum fsck_msg_id msg_id,
 {
int severity;
 
-   if (options-msg_severity  msg_id = 0  msg_id  FSCK_MSG_MAX)
+   if (options-msg_severity 
+   msg_id  FSCK_MSG_MIN  msg_id  FSCK_MSG_MAX)
severity = options-msg_severity[msg_id];
else {
severity = msg_id_info[msg_id].severity;
 
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Re: Git compile warnings (under mac/clang)

2015-01-23 Thread Jeff King
On Fri, Jan 23, 2015 at 01:38:17PM +0100, Johannes Schindelin wrote:

  Unless we are willing to drop the = 0 check completely. I think it is
  valid to do so regardless of the compiler's representation decision due
  to the numbering rules I mentioned above. It kind-of serves as a
  cross-check that we haven't cast some random int into the enum, but I
  think we would do better to find those callsites (since they are not
  guaranteed to work, anyway; in addition to signedness, it might choose a
  much smaller representation).
 
 Yeah, well, this check is really more of a safety net in case I messed
 up anything; I was saved so many times by my own defensive programming
 that I try to employ it as much as I can.

Yeah, I am all in favor of defensive programming. But I am not sure that
it is defending much here, as we silently fall back to an alternate
value for the severity. Would we notice, or would that produce subtly
wrong results? IOW, would this be better as:

  assert(msg_id = 0  msg_id  FSCK_MSG_MAX);

or something?

 -- snip --
 diff --git a/fsck.c b/fsck.c
 index 15cb8bd..8f8c82f 100644
 --- a/fsck.c
 +++ b/fsck.c
 @@ -107,7 +107,7 @@ static int fsck_msg_severity(enum fsck_msg_id msg_id,
  {
   int severity;
  
 - if (options-msg_severity  msg_id = 0  msg_id  FSCK_MSG_MAX)
 + if (options-msg_severity  ((unsigned int) msg_id)  FSCK_MSG_MAX)
   severity = options-msg_severity[msg_id];
   else {
   severity = msg_id_info[msg_id].severity;
 -- snap --
 
 What do you think? Michael, does this cause more Clang warnings, or would it 
 resolve the issue?

Hmm, yeah, that does not seem unreasonable, and is more localized.

-Peff
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Re: Git compile warnings (under mac/clang)

2015-01-23 Thread Johannes Schindelin
Hi Peff,

On 2015-01-23 13:23, Jeff King wrote:
 On Fri, Jan 23, 2015 at 12:48:29PM +0100, Johannes Schindelin wrote:
 
 Pointed out by Michael Blume. Jeff King provided the pointer to a commit
 fixing the same issue elsewhere in the Git source code.
 
 It may be useful to reference the exact commit (3ce3ffb8) to help people
 digging in the history (e.g., if we decide there is a better way to shut
 up this warning and we need to find all the places to undo the
 brain-damage).

Good point, thanks!

 -for (i = 0; i  FSCK_MSG_MAX; i++) {
 +for (i = FSCK_MSG_MIN + 1; i  FSCK_MSG_MAX; i++) {
 
 Ugh. It is really a shame how covering up this warning requires
 polluting so many places. I don't think we have a better way, though,
 aside from telling people to use -Wno-tautological-compare (and I can
 believe that it _is_ a useful warning in some other circumstances, so it
 seems a shame to lose it).
 
 Unless we are willing to drop the = 0 check completely. I think it is
 valid to do so regardless of the compiler's representation decision due
 to the numbering rules I mentioned above. It kind-of serves as a
 cross-check that we haven't cast some random int into the enum, but I
 think we would do better to find those callsites (since they are not
 guaranteed to work, anyway; in addition to signedness, it might choose a
 much smaller representation).

Yeah, well, this check is really more of a safety net in case I messed up 
anything; I was saved so many times by my own defensive programming that I try 
to employ it as much as I can.

But it does complicate the papering over Clang's overzealous warning, so I 
could live with removing the check altogether.

On the other hand, I could do something even easier:

-- snip --
diff --git a/fsck.c b/fsck.c
index 15cb8bd..8f8c82f 100644
--- a/fsck.c
+++ b/fsck.c
@@ -107,7 +107,7 @@ static int fsck_msg_severity(enum fsck_msg_id msg_id,
 {
int severity;
 
-   if (options-msg_severity  msg_id = 0  msg_id  FSCK_MSG_MAX)
+   if (options-msg_severity  ((unsigned int) msg_id)  FSCK_MSG_MAX)
severity = options-msg_severity[msg_id];
else {
severity = msg_id_info[msg_id].severity;
-- snap --

What do you think? Michael, does this cause more Clang warnings, or would it 
resolve the issue?

 I do not see either side of the bounds check here:
 
 +if (options-msg_severity 
 +msg_id  FSCK_MSG_MIN  msg_id  FSCK_MSG_MAX)
 
 as really doing anything. Any code which triggers it must already cause
 undefined behavior, I think (with the exception of msg_id == FSCK_MSG_MAX,
 but presumably that is something we never expect to happen, either).

Yep, it should not be triggered at all, but as I said, it is a nice defensive 
programming measure to avoid segmentation faults in case of a bug.

Ciao,
Dscho
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Re: Git compile warnings (under mac/clang)

2015-01-22 Thread Jeff King
On Thu, Jan 22, 2015 at 10:20:01PM +0100, Johannes Schindelin wrote:

 On 2015-01-22 20:59, Stefan Beller wrote:
  cc Johannes Schindelin johannes.schinde...@gmx.de who is working in
  the fsck at the moment
 
  On Thu, Jan 22, 2015 at 11:43 AM, Michael Blume blume.m...@gmail.com 
  wrote:
 
  CC fsck.o
  fsck.c:110:38: warning: comparison of unsigned enum expression = 0 is
  always true [-Wtautological-compare]
  if (options-msg_severity  msg_id = 0  msg_id  FSCK_MSG_MAX)
   ~~ ^  ~
 
 According to A2.5.4 of The C Programming Language 2nd edition:
 
 Identifiers declared as enumerators (see Par.A.8.4) are constants of type 
 int.
 
 Therefore, the warning is incorrect: any assumption about enum fsck_msg_id to 
 be unsigned is false.

I'm not sure that made it to ANSI. C99 says (setion 6.7.2.2, paragraph
4):

  Each enumerated type shall be compatible with char, a signed integer
  type, or an unsigned integer type. The choice of type is
  implementation-defined, but shall be capable of representing the
  values of all the members of the enumeration.

I don't have a copy of C89, but this isn't mentioned in the (very
cursory) list of changes found in C99. Anyway, that's academic.

I think we dealt with a similar situation before, in
3ce3ffb840a1dfa7fcbafa9309fab37478605d08.

-Peff
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Re: Git compile warnings (under mac/clang)

2015-01-22 Thread Stefan Beller
cc Johannes Schindelin johannes.schinde...@gmx.de who is working in
the fsck at the moment
cc Peter Wu pe...@lekensteyn.nl who worked on builtin/remote.c a few weeks ago

I just compiled origin/pu to test and also found a problem (doesn't
happen in origin/master):

http.c: In function 'get_preferred_languages':
http.c:1020:2: warning: implicit declaration of function 'setlocale'
[-Wimplicit-function-declaration]
  retval = setlocale(LC_MESSAGES, NULL);
  ^
http.c:1020:21: error: 'LC_MESSAGES' undeclared (first use in this function)
  retval = setlocale(LC_MESSAGES, NULL);
 ^
http.c:1020:21: note: each undeclared identifier is reported only once
for each function it appears in

so I cc Yi EungJun eungjun...@navercorp.com as well.

On Thu, Jan 22, 2015 at 11:43 AM, Michael Blume blume.m...@gmail.com wrote:
 These are probably minor, I only bring them up because Git's build is
 generally so quiet that it might be worth squashing these too.

 CC fsck.o
 fsck.c:110:38: warning: comparison of unsigned enum expression = 0 is
 always true [-Wtautological-compare]
 if (options-msg_severity  msg_id = 0  msg_id  FSCK_MSG_MAX)
  ~~ ^  ~
 1 warning generated.
 AR libgit.a
 /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/ranlib:
 file: libgit.a(gettext.o) has no symbols
 CC builtin/remote.o
 builtin/remote.c:1572:5: warning: add explicit braces to avoid
 dangling else [-Wdangling-else]
 else
 ^
 builtin/remote.c:1580:5: warning: add explicit braces to avoid
 dangling else [-Wdangling-else]
 else
 ^
 2 warnings generated.

 (the warning about libgit.a(gettext.o) is probably because I'm
 building with NO_GETTEXT -- I've never been able to get gettext to
 work on my mac)
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Re: Git compile warnings (under mac/clang)

2015-01-22 Thread Peter Wu
On Thursday 22 January 2015 11:59:54 Stefan Beller wrote:
 cc Johannes Schindelin johannes.schinde...@gmx.de who is working in
 the fsck at the moment
 cc Peter Wu pe...@lekensteyn.nl who worked on builtin/remote.c a few weeks 
 ago
 
 I just compiled origin/pu to test and also found a problem (doesn't
 happen in origin/master):
 
 http.c: In function 'get_preferred_languages':
 http.c:1020:2: warning: implicit declaration of function 'setlocale'
 [-Wimplicit-function-declaration]
   retval = setlocale(LC_MESSAGES, NULL);
   ^
 http.c:1020:21: error: 'LC_MESSAGES' undeclared (first use in this function)
   retval = setlocale(LC_MESSAGES, NULL);
  ^
 http.c:1020:21: note: each undeclared identifier is reported only once
 for each function it appears in
 
 so I cc Yi EungJun eungjun...@navercorp.com as well.
 
 On Thu, Jan 22, 2015 at 11:43 AM, Michael Blume blume.m...@gmail.com wrote:
  These are probably minor, I only bring them up because Git's build is
  generally so quiet that it might be worth squashing these too.
 
  CC fsck.o
  fsck.c:110:38: warning: comparison of unsigned enum expression = 0 is
  always true [-Wtautological-compare]
  if (options-msg_severity  msg_id = 0  msg_id  FSCK_MSG_MAX)
   ~~ ^  ~
  1 warning generated.
  AR libgit.a
  /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/ranlib:
  file: libgit.a(gettext.o) has no symbols
  CC builtin/remote.o
  builtin/remote.c:1572:5: warning: add explicit braces to avoid
  dangling else [-Wdangling-else]
  else
  ^
  builtin/remote.c:1580:5: warning: add explicit braces to avoid
  dangling else [-Wdangling-else]
  else
  ^
  2 warnings generated.

Hi, these warnings were present in v3 of the git-remote patch. v4 was
proposed to overcome these issues, but I have yet to respond to Junio's
feedback at http://www.spinics.net/lists/git/msg243652.html
(Message-ID: xmqqr3vx9ad5@gitster.dls.corp.google.com)

(cc'ing Junio to let him know I am still alive :p)

I'll get back to this next week, had some other tasks to prepare for.

Kind regards,
Peter

  (the warning about libgit.a(gettext.o) is probably because I'm
  building with NO_GETTEXT -- I've never been able to get gettext to
  work on my mac)

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Re: Git compile warnings (under mac/clang)

2015-01-22 Thread Johannes Schindelin
Hi Stefan,

On 2015-01-22 20:59, Stefan Beller wrote:
 cc Johannes Schindelin johannes.schinde...@gmx.de who is working in
 the fsck at the moment

 On Thu, Jan 22, 2015 at 11:43 AM, Michael Blume blume.m...@gmail.com wrote:

 CC fsck.o
 fsck.c:110:38: warning: comparison of unsigned enum expression = 0 is
 always true [-Wtautological-compare]
 if (options-msg_severity  msg_id = 0  msg_id  FSCK_MSG_MAX)
  ~~ ^  ~

According to A2.5.4 of The C Programming Language 2nd edition:

Identifiers declared as enumerators (see Par.A.8.4) are constants of type 
int.

Therefore, the warning is incorrect: any assumption about enum fsck_msg_id to 
be unsigned is false.

Ciao,
Johannes

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