small fixes for clang static analyzer

a few small things clang static analyzer found

.gitignore

@@ -1,3 +1,4 @@
+scan
 po/*.pot
 test-driver
 vips-*.tar.gz

README.md

@@ -56,8 +56,9 @@ Clang build:
 
 Clang static analysis:
 
-	$ CC=... scan-build ./configure ...
+	$ scan-build ./configure --disable-introspection
 	$ scan-build -o scan -v make 
+	$ scan-view scan/2013-11-22-2
 
 Clang dynamic analysis:
 

libvips/colour/LCh2Lab.c

@@ -62,11 +62,13 @@ G_DEFINE_TYPE( VipsLCh2Lab, vips_LCh2Lab, VIPS_TYPE_COLOUR_SPACE );
 static void
 vips_LCh2Lab_line( VipsColour *colour, VipsPel *out, VipsPel **in, int width )
 {		
-	float *p = (float *) in[0];
-	float *q = (float *) out;
-
+	float *p;
+	float *q;
 	int x;
 
+	p = (float *) in[0];
+	q = (float *) out;
+
 	for( x = 0; x < width; x++ ) {
 		float L = p[0];
 		float C = p[1];
@@ -81,6 +83,7 @@ vips_LCh2Lab_line( VipsColour *colour, VipsPel *out, VipsPel **in, int width )
 		q[0] = L;
 		q[1] = a;
 		q[2] = b;
+
 		q += 3;
 	}
 }
@@ -103,7 +106,7 @@ vips_col_Ch2ab( float C, float h, float *a, float *b )
 
 	in[1] = C;
 	in[2] = h;
-	x = in;
+	x = &in[0];
 	vips_LCh2Lab_line( NULL, (VipsPel *) out, (VipsPel **) &x, 1 );
 	*a = out[1];
 	*b = out[2];

libvips/colour/Lab2LCh.c

@@ -98,11 +98,13 @@ vips_col_ab2Ch( float a, float b, float *C, float *h )
 static void
 vips_Lab2LCh_line( VipsColour *colour, VipsPel *out, VipsPel **in, int width )
 {
-	float *p = (float *) in[0];
-	float *q = (float *) out;
-
+	float *p;
+	float *q;
 	int x;
 
+	p = (float *) in[0];
+	q = (float *) out;
+
 	for( x = 0; x < width; x++ ) {
 		float L = p[0];
 		float a = p[1];

libvips/conversion/cast.c

@@ -172,7 +172,7 @@ vips_cast_start( VipsImage *out, void *a, void *b )
 	seq->underflow = 0;
 
 	if( !seq->ir ) {
-		vips_cast_stop( seq, NULL, NULL );
+		vips_cast_stop( seq, a, b );
 		return( NULL );
 	}
 

libvips/conversion/rot45.c

@@ -236,7 +236,6 @@ vips_rot45_build( VipsObject *object )
 
 	case VIPS_ANGLE45_45:
 		vips_rot45_rot45( t[0], from );
-		from = t[0];
 		break;
 
 	default:

libvips/foreign/csv.c

@@ -183,7 +183,7 @@ read_double( FILE *fp, const char whitemap[256], const char sepmap[256],
 	if( ch == '"' ) {
 		(void) fgetc( fp );
 		(void) skip_to_quote( fp );
-		ch = fgetc( fp );
+		(void) fgetc( fp );
 	}
 	else if( !sepmap[ch] && 
 		fscanf( fp, "%lf", out ) != 1 ) {
@@ -196,7 +196,7 @@ read_double( FILE *fp, const char whitemap[256], const char sepmap[256],
 
 		/* Step over the bad data to the next separator.
 		 */
-		ch = skip_to_sep( fp, sepmap );
+		(void) skip_to_sep( fp, sepmap );
 	}
 
 	/* Don't need to check result, we have read a field successfully.

libvips/foreign/fits.c

@@ -225,7 +225,6 @@ vips_fits_get_header( VipsFits *fits, VipsImage *out )
 		VIPS_DEBUG_MSG( "%d) %lld\n", i, fits->naxes[i] );
 #endif /*VIPS_DEBUG*/
 
-	width = 1;
 	height = 1;
 	bands = 1;
 	switch( fits->naxis ) {

libvips/foreign/matlab.c

@@ -157,7 +157,6 @@ mat2vips_get_header( matvar_t *var, VipsImage *im )
 	VipsInterpretation interpretation; 
 	int i;
 
-	width = 1;
 	height = 1;
 	bands = 1;
 	switch( var->rank ) {

libvips/foreign/tiff2vips.c

@@ -1424,8 +1424,11 @@ read_stripwise( ReadTiff *rtiff, VipsImage *out )
 
 	/* rows_per_strip can be 2 ** 32 - 1, meaning the whole image. Clip 
 	 * this down to ysize to avoid confusing vips. 
+	 *
+	 * And it musn't be zero.
 	 */
-	rtiff->rows_per_strip = VIPS_MIN( rtiff->rows_per_strip, t[0]->Ysize );
+	rtiff->rows_per_strip = 
+		VIPS_CLIP( 1, rtiff->rows_per_strip, t[0]->Ysize );
 
 #ifdef DEBUG
 	printf( "read_stripwise: rows_per_strip = %u\n", 

libvips/foreign/vips2tiff.c

@@ -1190,7 +1190,7 @@ write_tif_stripwise( TiffWrite *tw )
 static void
 delete_files( TiffWrite *tw )
 {
-	PyramidLayer *layer = tw->layer;
+	PyramidLayer *layer;
 
 	if( tw->bname ) {
 #ifndef DEBUG

libvips/histogram/hist_local.c

@@ -93,7 +93,8 @@ vips_hist_local_stop( void *vseq, void *a, void *b )
 	VipsImage *in = (VipsImage *) a;
 
 	VIPS_UNREF( seq->ir );
-	if( seq->hist ) {
+	if( seq->hist &&
+		in ) {
 		int i; 
 
 		for( i = 0; i < in->Bands; i++ )

libvips/inplace/flood.c

@@ -127,10 +127,9 @@ typedef struct {
 static Buffer *
 buffer_build( void )
 {
-	Buffer *buf = IM_NEW( NULL, Buffer );
+	Buffer *buf;
 
-	if( !buf )
-		return( NULL );
+	buf = g_new( Buffer, 1 );
 	buf->next = NULL;
 	buf->n = 0;
 
@@ -146,7 +145,7 @@ buffer_free( Buffer *buf )
 		Buffer *p;
 
 		p = buf->next;
-		im_free( buf );
+		g_free( buf );
 		buf = p;
 	}
 }
@@ -175,8 +174,7 @@ buffer_add( Buffer *buf, Flood *flood, int x1, int x2, int y, int dir )
 	if( buf->n == PBUFSIZE ) { 
 		Buffer *new;
 
-		if( !(new = buffer_build()) ) 
-			return( NULL ); 
+		new = buffer_build();
 		new->next = buf;
 		buf = new;
 	} 
@@ -382,13 +380,10 @@ flood_new( IMAGE *image, IMAGE *test, int x, int y, VipsPel *ink, Rect *dout )
 	flood->top = y;
 	flood->right = x;
 	flood->bottom = y;
+	flood->in = buffer_build();
+	flood->out = buffer_build();
 
-	flood->in = NULL;
-	flood->out = NULL;
-
-	if( !(flood->edge = (VipsPel *) im_malloc( NULL, flood->tsize )) ||
-		!(flood->in = buffer_build()) ||
-		!(flood->out = buffer_build()) ) {
+	if( !(flood->edge = (VipsPel *) im_malloc( NULL, flood->tsize )) ) {
 		flood_free( flood );
 		return( NULL );
 	}

libvips/iofuncs/operation.c

@@ -555,6 +555,9 @@ vips_call_required_optional( VipsOperation **operation,
 	va_end( a );
 	va_end( b );
 
+	if( result )
+		return( -1 );
+
 	/* Build from cache.
 	 */
 	if( vips_cache_operation_buildp( operation ) )