[U-Boot] [PATCH v3] Add assert() for debug assertions

[U-Boot] [PATCH v3] Add assert() for debug assertions

[Simon Glass]

assert() is like BUG_ON() but compiles to nothing unless DEBUG is defined.
This is useful when a condition is an error but a board reset is unlikely
to fix it, so it is better to soldier on in hope. Assertion failures should
be caught during development/test.

It turns out that assert() is defined separately in a few places in U-Boot
with various meanings. This patch cleans up some of these.

Build errors exposed by this change (and defining DEBUG) are also fixed in
this patch.

Signed-off-by: Simon Glass <sjg@chromium.org>
---
Changes in v2:
- Changed macros so that all code is compiled even if DEBUG is disabled

Changes in v3:
- Use panic() instead of printf()
- Use separate __assert_fail() function to reduce memory footprint
- Changed output format to match assert(3)

 common/dlmalloc.c |    7 -------
 include/common.h  |   21 +++++++++++++++++++++
 include/malloc.h  |    8 --------
 lib/qsort.c       |    5 -----
 lib/vsprintf.c    |    8 ++++++++
 5 files changed, 29 insertions(+), 20 deletions(-)

diff --git a/common/dlmalloc.c b/common/dlmalloc.c
index e9bab09..f2080c6 100644
--- a/common/dlmalloc.c
+++ b/common/dlmalloc.c
@@ -286,13 +286,6 @@ extern "C" {
 
 */
 
-#ifdef DEBUG
-#include <assert.h>
-#else
-#define assert(x) ((void)0)
-#endif
-
-
 /*
   INTERNAL_SIZE_T is the word-size used for internal bookkeeping
   of chunk sizes. On a 64-bit machine, you can reduce malloc
diff --git a/include/common.h b/include/common.h
index 1e21b7a..0956b93 100644
--- a/include/common.h
+++ b/include/common.h
@@ -124,6 +124,27 @@ typedef volatile unsigned char	vu_char;
 #define debugX(level,fmt,args...)
 #endif	/* DEBUG */
 
+#ifdef DEBUG
+# define _DEBUG 1
+#else
+# define _DEBUG 0
+#endif
+
+/*
+ * An assertion is run-time check done in debug mode only. If DEBUG is not
+ * defined then it is skipped. If DEBUG is defined and the assertion fails,
+ * then it calls panic*( which may or may not reset/halt U-Boot (see
+ * CONFIG_PANIC_HANG), It is hoped that all failing assertions are found
+ * before release, and after release it is hoped that they don't matter. But
+ * in any case these failing assertions cannot be fixed with a reset (which
+ * may just do the same assertion again).
+ */
+void __assert_fail(const char *assertion, const char *file, unsigned line,
+		   const char *function);
+#define assert(x) \
+	({ if (!(x) && _DEBUG) \
+		__assert_fail(#x, __FILE__, __LINE__, __func__); })
+
 #define error(fmt, args...) do {					\
 		printf("ERROR: " fmt "\nat %s:%d/%s()\n",		\
 			##args, __FILE__, __LINE__, __func__);		\
diff --git a/include/malloc.h b/include/malloc.h
index 3e145ad..ecf3c67 100644
--- a/include/malloc.h
+++ b/include/malloc.h
@@ -285,14 +285,6 @@ extern "C" {
 
 */
 
-#ifdef DEBUG
-/* #include <assert.h> */
-#define assert(x) ((void)0)
-#else
-#define assert(x) ((void)0)
-#endif
-
-
 /*
   INTERNAL_SIZE_T is the word-size used for internal bookkeeping
   of chunk sizes. On a 64-bit machine, you can reduce malloc
diff --git a/lib/qsort.c b/lib/qsort.c
index 1cc0d31..86c392c 100644
--- a/lib/qsort.c
+++ b/lib/qsort.c
@@ -17,11 +17,6 @@
 
 #include <linux/types.h>
 #include <exports.h>
-#if 0
-#include <assert.h>
-#else
-#define assert(arg)
-#endif
 
 void qsort(void  *base,
 	   size_t nel,
diff --git a/lib/vsprintf.c b/lib/vsprintf.c
index 3b924ec..1f01b70 100644
--- a/lib/vsprintf.c
+++ b/lib/vsprintf.c
@@ -728,3 +728,11 @@ void panic(const char *fmt, ...)
 	do_reset (NULL, 0, 0, NULL);
 #endif
 }
+
+void __assert_fail(const char *assertion, const char *file, unsigned line,
+		   const char *function)
+{
+	/* This will not return */
+	panic("%s:%u: %s: Assertion `%s' failed.", file, line, function,
+	      assertion);
+}
-- 
1.7.3.1

[U-Boot] [PATCH v3] Add assert() for debug assertions

[Mike Frysinger]

On Wednesday, June 29, 2011 15:49:34 Simon Glass wrote:
> - Use separate __assert_fail() function to reduce memory footprint

do we really care about that when people are using #define DEBUG ?  i'd say 
this is an unnecessary indirection ...
-mike
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[U-Boot] [PATCH v3] Add assert() for debug assertions

[Wolfgang Denk]

Dear Mike Frysinger,

In message <201106291643.32477.vapier@gentoo.org> you wrote:
>
> do we really care about that when people are using #define DEBUG ?  i'd say
> this is an unnecessary indirection ...

Yes, we do care about the memory footprint - no matter whether with or
without DEBUG.

Best regards,

Wolfgang Denk

-- 
DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
Those who do not  understand  Unix  are  condemned  to  reinvent  it,
poorly.              - Henry Spencer, University of Toronto Unix hack

[U-Boot] [PATCH v3] Add assert() for debug assertions

[Mike Frysinger]

On Wednesday, June 29, 2011 17:01:23 Wolfgang Denk wrote:
> Mike Frysinger wrote:
> > do we really care about that when people are using #define DEBUG ?  i'd
> > say this is an unnecessary indirection ...
> 
> Yes, we do care about the memory footprint - no matter whether with or
> without DEBUG.

there's caring about it, and there's nitpicking over ~10 bytes per call site.
-mike
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[U-Boot] [PATCH v3] Add assert() for debug assertions

[Simon Glass]

Did this go anywhere? I will resend... - Simon

On Wed, Jun 29, 2011 at 2:54 PM, Mike Frysinger <vapier@gentoo.org> wrote:
> On Wednesday, June 29, 2011 17:01:23 Wolfgang Denk wrote:
>> Mike Frysinger wrote:
>> > do we really care about that when people are using #define DEBUG ? ?i'd
>> > say this is an unnecessary indirection ...
>>
>> Yes, we do care about the memory footprint - no matter whether with or
>> without DEBUG.
>
> there's caring about it, and there's nitpicking over ~10 bytes per call site.
> -mike
>

[U-Boot] [PATCH v3] Add assert() for debug assertions

[Mike Frysinger]

On Wednesday, September 07, 2011 18:29:16 Simon Glass wrote:
> On Wed, Jun 29, 2011 at 2:54 PM, Mike Frysinger <vapier@gentoo.org> wrote:
> > On Wednesday, June 29, 2011 17:01:23 Wolfgang Denk wrote:
> >> Mike Frysinger wrote:
> >> > do we really care about that when people are using #define DEBUG ?
> >> >  i'd say this is an unnecessary indirection ...
> >> 
> >> Yes, we do care about the memory footprint - no matter whether with or
> >> without DEBUG.
> > 
> > there's caring about it, and there's nitpicking over ~10 bytes per call
> > site.
>
> Did this go anywhere? I will resend...

i dont care enough to fight wolfgang over it
-mike
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[U-Boot] [PATCH v3] Add assert() for debug assertions

[Simon Glass]

Hi Mike / Wolfgang,

On Thu, Sep 8, 2011 at 5:34 PM, Mike Frysinger <vapier@gentoo.org> wrote:
> On Wednesday, September 07, 2011 18:29:16 Simon Glass wrote:
>> On Wed, Jun 29, 2011 at 2:54 PM, Mike Frysinger <vapier@gentoo.org> wrote:
>> > On Wednesday, June 29, 2011 17:01:23 Wolfgang Denk wrote:
>> >> Mike Frysinger wrote:
>> >> > do we really care about that when people are using #define DEBUG ?
>> >> > ?i'd say this is an unnecessary indirection ...
>> >>
>> >> Yes, we do care about the memory footprint - no matter whether with or
>> >> without DEBUG.
>> >
>> > there's caring about it, and there's nitpicking over ~10 bytes per call
>> > site.
>>
>> Did this go anywhere? I will resend...
>
> i dont care enough to fight wolfgang over it

OK. Any other comments on this Wolfgang or is this finished?

Regards,
Simon

> -mike
>

[U-Boot] [PATCH v3] Add assert() for debug assertions

[Wolfgang Denk]

Dear Simon Glass,

In message <1309376974-12943-1-git-send-email-sjg@chromium.org> you wrote:
> assert() is like BUG_ON() but compiles to nothing unless DEBUG is defined.
> This is useful when a condition is an error but a board reset is unlikely
> to fix it, so it is better to soldier on in hope. Assertion failures should
> be caught during development/test.
> 
> It turns out that assert() is defined separately in a few places in U-Boot
> with various meanings. This patch cleans up some of these.
> 
> Build errors exposed by this change (and defining DEBUG) are also fixed in
> this patch.
> 
> Signed-off-by: Simon Glass <sjg@chromium.org>
> ---
> Changes in v2:
> - Changed macros so that all code is compiled even if DEBUG is disabled
> 
> Changes in v3:
> - Use panic() instead of printf()
> - Use separate __assert_fail() function to reduce memory footprint
> - Changed output format to match assert(3)
> 
>  common/dlmalloc.c |    7 -------
>  include/common.h  |   21 +++++++++++++++++++++
>  include/malloc.h  |    8 --------
>  lib/qsort.c       |    5 -----
>  lib/vsprintf.c    |    8 ++++++++
>  5 files changed, 29 insertions(+), 20 deletions(-)

Applied, thanks.

Best regards,

Wolfgang Denk

-- 
DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
How can you tell when sour cream goes bad?

[U-Boot] [PATCH] Fix warning: "assert" redefined

[Wolfgang Denk]

Commit 21726a7 "Add assert() for debug assertions" caused build
warnings for many systems:

In file included from bedbug.c:6:
/home/wd/git/u-boot/work/include/bedbug/bedbug.h:24:1: warning: "assert" redefined
In file included from bedbug.c:3:
/home/wd/git/u-boot/work/include/common.h:144:1: warning: this is the location of the previous definition
In file included from cmd_bedbug.c:10:
/home/wd/git/u-boot/work/include/bedbug/bedbug.h:24:1: warning: "assert" redefined
In file included from cmd_bedbug.c:5:
/home/wd/git/u-boot/work/include/common.h:144:1: warning: this is the location of the previous definition

Signed-off-by: Wolfgang Denk <wd@denx.de>
Cc: Simon Glass <sjg@chromium.org>
---
 include/bedbug/bedbug.h |    2 --
 1 files changed, 0 insertions(+), 2 deletions(-)

diff --git a/include/bedbug/bedbug.h b/include/bedbug/bedbug.h
index 471215e..0c5d687 100644
--- a/include/bedbug/bedbug.h
+++ b/include/bedbug/bedbug.h
@@ -21,8 +21,6 @@
 #endif
 #endif
 
-#define assert( condition ) if( (condition) ) _exit(0)
-
 #endif /* _BEDBUG_H */
 
 
-- 
1.7.6

[U-Boot] [PATCH] Fix warning: "assert" redefined

[Simon Glass]

Hi Wolfgang,

On Fri, Sep 9, 2011 at 3:38 PM, Wolfgang Denk <wd@denx.de> wrote:
> Commit 21726a7 "Add assert() for debug assertions" caused build
> warnings for many systems:
>
> In file included from bedbug.c:6:
> /home/wd/git/u-boot/work/include/bedbug/bedbug.h:24:1: warning: "assert" redefined
> In file included from bedbug.c:3:
> /home/wd/git/u-boot/work/include/common.h:144:1: warning: this is the location of the previous definition
> In file included from cmd_bedbug.c:10:
> /home/wd/git/u-boot/work/include/bedbug/bedbug.h:24:1: warning: "assert" redefined
> In file included from cmd_bedbug.c:5:
> /home/wd/git/u-boot/work/include/common.h:144:1: warning: this is the location of the previous definition
>

I was wondering about that one :-) Thank you. I also ignored ubifs
since it seemed to have its own system, and one in yaffs which was
commented out. If it helps:

Acked-by: Simon Glass <sjg@chromium.org>

Regards,
Simon

> Signed-off-by: Wolfgang Denk <wd@denx.de>
> Cc: Simon Glass <sjg@chromium.org>
> ---
> ?include/bedbug/bedbug.h | ? ?2 --
> ?1 files changed, 0 insertions(+), 2 deletions(-)
>
> diff --git a/include/bedbug/bedbug.h b/include/bedbug/bedbug.h
> index 471215e..0c5d687 100644
> --- a/include/bedbug/bedbug.h
> +++ b/include/bedbug/bedbug.h
> @@ -21,8 +21,6 @@
> ?#endif
> ?#endif
>
> -#define assert( condition ) if( (condition) ) _exit(0)
> -
> ?#endif /* _BEDBUG_H */
>
>
> --
> 1.7.6
>
>

[U-Boot] [PATCH] utx8245: fix build breakage due to assert()

[Wolfgang Denk]

Commit 21726a7 "Add assert() for debug assertions" broke building the
utx8245 board:

dlmalloc.c: In function 'do_check_chunk':
dlmalloc.c:1660: error: 'sz' undeclared (first use in this function)
dlmalloc.c:1660: error: (Each undeclared identifier is reported only once
dlmalloc.c:1660: error: for each function it appears in.)
dlmalloc.c: In function 'do_check_free_chunk':
dlmalloc.c:1689: error: 'next' undeclared (first use in this function)
dlmalloc.c: In function 'do_check_malloced_chunk':
dlmalloc.c:1748: error: 'sz' undeclared (first use in this function)
dlmalloc.c:1750: error: 'room' undeclared (first use in this function)

Signed-off-by: Wolfgang Denk <wd@denx.de>
Cc: Simon Glass <sjg@chromium.org>
---
 common/dlmalloc.c |    6 ------
 1 files changed, 0 insertions(+), 6 deletions(-)

diff --git a/common/dlmalloc.c b/common/dlmalloc.c
index f2080c6..c645d73 100644
--- a/common/dlmalloc.c
+++ b/common/dlmalloc.c
@@ -1647,9 +1647,7 @@ static void do_check_chunk(mchunkptr p)
 static void do_check_chunk(p) mchunkptr p;
 #endif
 {
-#if 0	/* causes warnings because assert() is off */
   INTERNAL_SIZE_T sz = p->size & ~PREV_INUSE;
-#endif	/* 0 */
 
   /* No checkable chunk is mmapped */
   assert(!chunk_is_mmapped(p));
@@ -1671,9 +1669,7 @@ static void do_check_free_chunk(p) mchunkptr p;
 #endif
 {
   INTERNAL_SIZE_T sz = p->size & ~PREV_INUSE;
-#if 0	/* causes warnings because assert() is off */
   mchunkptr next = chunk_at_offset(p, sz);
-#endif	/* 0 */
 
   do_check_chunk(p);
 
@@ -1737,10 +1733,8 @@ static void do_check_malloced_chunk(mchunkptr p, INTERNAL_SIZE_T s)
 static void do_check_malloced_chunk(p, s) mchunkptr p; INTERNAL_SIZE_T s;
 #endif
 {
-#if 0	/* causes warnings because assert() is off */
   INTERNAL_SIZE_T sz = p->size & ~PREV_INUSE;
   long room = sz - s;
-#endif	/* 0 */
 
   do_check_inuse_chunk(p);
 
-- 
1.7.6

[U-Boot] [PATCH] tegra2: fix warning: "assert" redefined

[Wolfgang Denk]

Commit 21726a7 "Add assert() for debug assertions" caused build
warnings for all tegra2 based boards:

clock.c:36:1: warning: "assert" redefined
In file included from clock.c:29:
include/common.h:144:1: warning: this is the location of the previous definition

Signed-off-by: Wolfgang Denk <wd@denx.de>
Cc: Simon Glass <sjg@chromium.org>
---
 arch/arm/cpu/armv7/tegra2/clock.c |    8 --------
 1 files changed, 0 insertions(+), 8 deletions(-)

diff --git a/arch/arm/cpu/armv7/tegra2/clock.c b/arch/arm/cpu/armv7/tegra2/clock.c
index 67eed14..0aaed7d 100644
--- a/arch/arm/cpu/armv7/tegra2/clock.c
+++ b/arch/arm/cpu/armv7/tegra2/clock.c
@@ -28,14 +28,6 @@
 #include <asm/arch/tegra2.h>
 #include <common.h>
 
-#ifdef DEBUG
-#define assert(x)	\
-	({ if (!(x)) printf("Assertion failure '%s' %s line %d\n", \
-		#x, __FILE__, __LINE__); })
-#else
-#define assert(x)
-#endif
-
 /*
  * Get the oscillator frequency, from the corresponding hardware configuration
  * field.
-- 
1.7.6

[U-Boot] [PATCH] Fix warning: "assert" redefined

[Wolfgang Denk]

Dear Wolfgang Denk,

In message <1315607922-7285-1-git-send-email-wd@denx.de> you wrote:
> Commit 21726a7 "Add assert() for debug assertions" caused build
> warnings for many systems:
> 
> In file included from bedbug.c:6:
> /home/wd/git/u-boot/work/include/bedbug/bedbug.h:24:1: warning: "assert" redefined
> In file included from bedbug.c:3:
> /home/wd/git/u-boot/work/include/common.h:144:1: warning: this is the location of the previous definition
> In file included from cmd_bedbug.c:10:
> /home/wd/git/u-boot/work/include/bedbug/bedbug.h:24:1: warning: "assert" redefined
> In file included from cmd_bedbug.c:5:
> /home/wd/git/u-boot/work/include/common.h:144:1: warning: this is the location of the previous definition
> 
> Signed-off-by: Wolfgang Denk <wd@denx.de>
> Cc: Simon Glass <sjg@chromium.org>
> ---
>  include/bedbug/bedbug.h |    2 --
>  1 files changed, 0 insertions(+), 2 deletions(-)

Applied, thanks.

Best regards,

Wolfgang Denk

-- 
DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
I've been programming for (35-9=) 24 years myself,  and  I  find  the
best way to learn a new language is to *read* every example snippet I
can find, with a reference book close by. Eventually, the *rhythm* of
the language starts pounding in my head... and my fluency is close at
hand. That's how I learned Perl, and now I'm one of the drummers. :-)
         -- Randal L. Schwartz in <8cvi6p2tir.fsf@gadget.cscaper.com>

[U-Boot] [PATCH] utx8245: fix build breakage due to assert()

[Wolfgang Denk]

Dear Wolfgang Denk,

In message <1315663665-24926-1-git-send-email-wd@denx.de> you wrote:
> Commit 21726a7 "Add assert() for debug assertions" broke building the
> utx8245 board:
> 
> dlmalloc.c: In function 'do_check_chunk':
> dlmalloc.c:1660: error: 'sz' undeclared (first use in this function)
> dlmalloc.c:1660: error: (Each undeclared identifier is reported only once
> dlmalloc.c:1660: error: for each function it appears in.)
> dlmalloc.c: In function 'do_check_free_chunk':
> dlmalloc.c:1689: error: 'next' undeclared (first use in this function)
> dlmalloc.c: In function 'do_check_malloced_chunk':
> dlmalloc.c:1748: error: 'sz' undeclared (first use in this function)
> dlmalloc.c:1750: error: 'room' undeclared (first use in this function)
> 
> Signed-off-by: Wolfgang Denk <wd@denx.de>
> Cc: Simon Glass <sjg@chromium.org>
> ---
>  common/dlmalloc.c |    6 ------
>  1 files changed, 0 insertions(+), 6 deletions(-)

Applied, thanks.

Best regards,

Wolfgang Denk

-- 
DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
You can't evaluate a man by logic alone.
	-- McCoy, "I, Mudd", stardate 4513.3

[U-Boot] [PATCH] tegra2: fix warning: "assert" redefined

[Wolfgang Denk]

Dear Wolfgang Denk,

In message <1315664363-3979-1-git-send-email-wd@denx.de> you wrote:
> Commit 21726a7 "Add assert() for debug assertions" caused build
> warnings for all tegra2 based boards:
> 
> clock.c:36:1: warning: "assert" redefined
> In file included from clock.c:29:
> include/common.h:144:1: warning: this is the location of the previous definition
> 
> Signed-off-by: Wolfgang Denk <wd@denx.de>
> Cc: Simon Glass <sjg@chromium.org>
> ---
>  arch/arm/cpu/armv7/tegra2/clock.c |    8 --------
>  1 files changed, 0 insertions(+), 8 deletions(-)

Applied, thanks.

Best regards,

Wolfgang Denk

-- 
DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
"More software projects have gone awry for lack of calendar time than
for all other causes combined."
                         - Fred Brooks, Jr., _The Mythical Man Month_

[U-Boot] [PATCH] tegra2: fix warning: "assert" redefined

[Simon Glass]

Hi Wolfgang,

On Sat, Sep 10, 2011 at 1:44 PM, Wolfgang Denk <wd@denx.de> wrote:
> Dear Wolfgang Denk,
>
> In message <1315664363-3979-1-git-send-email-wd@denx.de> you wrote:
>> Commit 21726a7 "Add assert() for debug assertions" caused build
>> warnings for all tegra2 based boards:
>>
>> clock.c:36:1: warning: "assert" redefined
>> In file included from clock.c:29:
>> include/common.h:144:1: warning: this is the location of the previous definition

Thanks again. The patch set I just sent out modifies the assert() in
this file, but I will remove it in V2.

Regards,
Simon

>>
>> Signed-off-by: Wolfgang Denk <wd@denx.de>
>> Cc: Simon Glass <sjg@chromium.org>
>> ---
>> ?arch/arm/cpu/armv7/tegra2/clock.c | ? ?8 --------
>> ?1 files changed, 0 insertions(+), 8 deletions(-)
>
> Applied, thanks.
>
> Best regards,
>
> Wolfgang Denk
>
> --
> DENX Software Engineering GmbH, ? ? MD: Wolfgang Denk & Detlev Zundel
> HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
> Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
> "More software projects have gone awry for lack of calendar time than
> for all other causes combined."
> ? ? ? ? ? ? ? ? ? ? ? ? - Fred Brooks, Jr., _The Mythical Man Month_
>