Enable -Wpedantic

Fix a few warnings related needed to build the source with this option.

Add new exception to .checkpatch.conf.

Signed-off-by: Antonio Niño Díaz <antonio_nd@outlook.com>

.checkpatch.conf

@@ -53,6 +53,9 @@
 # Prefer stdint.h types over kernel types
 --ignore PREFER_KERNEL_TYPES
 
+# Don't ask to replace sscanf by kstrto
+--ignore SSCANF_TO_KSTRTO
+
 # Parentheses can make the code clearer
 --ignore UNNECESSARY_PARENTHESES
 

Makefile

@@ -26,7 +26,7 @@ PNGLDLIBS	:= `${PKG_CONFIG} --static --libs-only-l libpng`
 
 VERSION_STRING	:= `git describe --tags --dirty --always 2>/dev/null`
 
-WARNFLAGS	:= -Wall -Werror
+WARNFLAGS	:= -Werror -Wall -Wpedantic
 
 # Overridable CFLAGS
 CFLAGS		:= -g

src/asm/lexer.c

@@ -640,7 +640,6 @@ scanagain:
 
 	/* Check for line continuation character */
 	if (*pLexBuffer == '\\') {
-
 		/*
 		 * Look for line continuation character after a series of
 		 * spaces. This is also useful for files that use Windows line

src/asm/main.c

@@ -147,10 +147,13 @@ void opt_Parse(char *s)
 	case 'z':
 		if (strlen(&s[1]) <= 2) {
 			int32_t result;
+			unsigned int fillchar;
 
-			result = sscanf(&s[1], "%x", &newopt.fillchar);
+			result = sscanf(&s[1], "%x", &fillchar);
 			if (!((result == EOF) || (result == 1)))
 				errx(1, "Invalid argument for option 'z'");
+
+			newopt.fillchar = fillchar;
 		} else {
 			errx(1, "Invalid argument for option 'z'");
 		}

src/gfx/makepng.c

@@ -317,9 +317,9 @@ static void rgba_png_palette(struct PNGImage *img,
 			     png_color **palette_ptr_ptr, int *num_colors)
 {
 	if (png_get_valid(img->png, img->info, PNG_INFO_PLTE))
-		return rgba_PLTE_palette(img, palette_ptr_ptr, num_colors);
+		rgba_PLTE_palette(img, palette_ptr_ptr, num_colors);
 	else
-		return rgba_build_palette(img, palette_ptr_ptr, num_colors);
+		rgba_build_palette(img, palette_ptr_ptr, num_colors);
 }
 
 static void rgba_PLTE_palette(struct PNGImage *img,