[PATCH 0/4] build system fixes

[PATCH 0/4] build system fixes

[Eric Wong]

Perl (as distributed by Debian) disables assertions and
enables fewer warnings than I'd like.  Now, I'm using config.mak
to set a bunch of warnings and seeing some noise, these fix it.

Eric Wong (4):
  Makefile.PL: remove CCFLAGS overrides
  workaround -DNDEBUG warnings
  quiet uninitialized variable warnings
  avoid mixing declarations and code

 Makefile.PL |  7 -------
 Mwrap.xs    | 26 +++++++++++++++-----------
 2 files changed, 15 insertions(+), 18 deletions(-)

[PATCH 1/4] Makefile.PL: remove CCFLAGS overrides

[Eric Wong]

From: Eric Wong <e@80x24.org>

Blindly copied from a C++ project :P
---
 Makefile.PL | 7 -------
 1 file changed, 7 deletions(-)

diff --git a/Makefile.PL b/Makefile.PL
index dc7d6dd..a7d131d 100644
--- a/Makefile.PL
+++ b/Makefile.PL
@@ -29,12 +29,6 @@ END
 # may be empty
 chomp(my $INC = `$pkg_config --cflags liburcu-cds liburcu-bp`);
 my @writemakefile_args = ();
-# Filter out some gcc options which g++ doesn't support.
-my $CCFLAGS = $Config{ccflags};
-
-if (defined $ENV{CPPFLAGS}) {
-	$CCFLAGS .= ' ' . $ENV{CPPFLAGS};
-}
 
 # See lib/ExtUtils/MakeMaker.pm for details of how to influence
 # the contents of the Makefile that is written.
@@ -49,7 +43,6 @@ push @writemakefile_args, (
 	LICENSE => 'gpl_2', # GPL-2.0+, CPAN::Meta::Spec limitation
 	MIN_PERL_VERSION => '5.8.0',
 	BUILD_REQUIRES => {},
-	CCFLAGS => $CCFLAGS, # e.g -I/usr/include/$ARCH
 	INC => $INC,
 	depend => {
 		Makefile => 'lib/Devel/Mwrap.pm',

[PATCH 2/4] workaround -DNDEBUG warnings

[Eric Wong]

From: Eric Wong <e@80x24.org>

Perl defaults to building with -DNDEBUG, which causes unused
variable warnings to show up when we use -Wall in CCFLAGS.
---
 Mwrap.xs | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/Mwrap.xs b/Mwrap.xs
index b81dfc0..8ce7b46 100644
--- a/Mwrap.xs
+++ b/Mwrap.xs
@@ -133,6 +133,9 @@ mutex_lock(pthread_mutex_t *m)
 {
 	int err = pthread_mutex_lock(m);
 	assert(err == 0);
+#ifdef NDEBUG
+	(void)err; /* quiet gcc warning */
+#endif
 }
 
 static void
@@ -140,6 +143,9 @@ mutex_unlock(pthread_mutex_t *m)
 {
 	int err = pthread_mutex_unlock(m);
 	assert(err == 0);
+#ifdef NDEBUG
+	(void)err; /* quiet gcc warning */
+#endif
 }
 
 #ifndef HAVE_MEMPCPY

[PATCH 3/4] quiet uninitialized variable warnings

[Eric Wong]

From: Eric Wong <e@80x24.org>

-Wmaybe-uninitialized (tested gcc 8.3.0) needlessly warns about
this, but it's a good simplification nevertheless.
---
 Mwrap.xs | 10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/Mwrap.xs b/Mwrap.xs
index 8ce7b46..4d346ab 100644
--- a/Mwrap.xs
+++ b/Mwrap.xs
@@ -469,16 +469,14 @@ internal_memalign(void **pp, size_t alignment, size_t size, uintptr_t caller)
 static void *
 memalign_result(int err, void *p)
 {
-	if (caa_unlikely(err)) {
+	if (caa_unlikely(err))
 		errno = err;
-		return 0;
-	}
 	return p;
 }
 
 void *memalign(size_t alignment, size_t size)
 {
-	void *p;
+	void *p = NULL;
 	int err = internal_memalign(&p, alignment, size, RETURN_ADDRESS(0));
 	return memalign_result(err, p);
 }
@@ -493,7 +491,7 @@ void cfree(void *) __attribute__((alias("free")));
 
 void *valloc(size_t size)
 {
-	void *p;
+	void *p = NULL;
 	int err = internal_memalign(&p, page_size, size, RETURN_ADDRESS(0));
 	return memalign_result(err, p);
 }
@@ -511,7 +509,7 @@ void *valloc(size_t size)
 void *pvalloc(size_t size)
 {
 	size_t alignment = page_size;
-	void *p;
+	void *p = NULL;
 	int err;
 
 	if (add_overflow_p(size, alignment)) {

[PATCH 4/4] avoid mixing declarations and code

[Eric Wong]

From: Eric Wong <e@80x24.org>

This quiets warnings when using -Wdeclaration-after-statement
which is still common in some circles.
---
 Mwrap.xs | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/Mwrap.xs b/Mwrap.xs
index 4d346ab..09d5581 100644
--- a/Mwrap.xs
+++ b/Mwrap.xs
@@ -851,8 +851,8 @@ PREINIT:
 	struct cds_lfht_node *cur;
 	struct cds_lfht *t;
 	struct src_loc *l = NULL;
-	++locating;
 CODE:
+	++locating;
 	if (!SvPOK(loc))
 		XSRETURN_UNDEF;
 	str = SvPV(loc, len);
@@ -897,8 +897,8 @@ size_t
 src_loc_frees(self)
 	Devel::Mwrap::SrcLoc self
 PREINIT:
-	++locating;
 CODE:
+	++locating;
 	RETVAL = uatomic_read(&self->frees);
 OUTPUT:
 	RETVAL
@@ -909,8 +909,8 @@ size_t
 src_loc_allocations(self)
 	Devel::Mwrap::SrcLoc self
 PREINIT:
-	++locating;
 CODE:
+	++locating;
 	RETVAL = uatomic_read(&self->allocations);
 OUTPUT:
 	RETVAL
@@ -921,8 +921,8 @@ size_t
 src_loc_total(self)
 	Devel::Mwrap::SrcLoc self
 PREINIT:
-	++locating;
 CODE:
+	++locating;
 	RETVAL = uatomic_read(&self->total);
 OUTPUT:
 	RETVAL
@@ -933,8 +933,8 @@ SV *
 src_loc_name(self)
 	Devel::Mwrap::SrcLoc self
 PREINIT:
-	++locating;
 CODE:
+	++locating;
 	RETVAL = location_string(self);
 OUTPUT:
 	RETVAL