Merge tag 'kbuild-v4.16' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild updates from Masahiro Yamada:

 - terminate the build correctly in case of fixdep errors

 - clean up fixdep

 - suppress packed-not-aligned warnings from GCC-8

 - fix W= handling for extra DTC warnings

* tag 'kbuild-v4.16' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  kbuild: fix W= option checks for extra DTC warnings
  Kbuild: suppress packed-not-aligned warning for default setting only
  fixdep: use existing helper to check modular CONFIG options
  fixdep: refactor parse_dep_file()
  fixdep: move global variables to local variables of main()
  fixdep: remove unneeded memcpy() in parse_dep_file()
  fixdep: factor out common code for reading files
  fixdep: use malloc() and read() to load dep_file to buffer
  fixdep: remove unnecessary <arpa/inet.h> inclusion
  fixdep: exit with error code in error branches of do_config_file()

scripts/Makefile.extrawarn

@@ -11,6 +11,8 @@
 # are not supported by all versions of the compiler
 # ==========================================================================
 
+KBUILD_CFLAGS += $(call cc-disable-warning, packed-not-aligned)
+
 ifeq ("$(origin W)", "command line")
   export KBUILD_ENABLE_EXTRA_GCC_CHECKS := $(W)
 endif
@@ -26,6 +28,7 @@ warning-1 += -Wold-style-definition
 warning-1 += $(call cc-option, -Wmissing-include-dirs)
 warning-1 += $(call cc-option, -Wunused-but-set-variable)
 warning-1 += $(call cc-option, -Wunused-const-variable)
+warning-1 += $(call cc-option, -Wpacked-not-aligned)
 warning-1 += $(call cc-disable-warning, missing-field-initializers)
 warning-1 += $(call cc-disable-warning, sign-compare)
 

scripts/Makefile.lib

@@ -264,7 +264,7 @@ cmd_gzip = (cat $(filter-out FORCE,$^) | gzip -n -f -9 > $@) || \
 DTC ?= $(objtree)/scripts/dtc/dtc
 
 # Disable noisy checks by default
-ifeq ($(KBUILD_ENABLE_EXTRA_GCC_CHECKS),)
+ifeq ($(findstring 1,$(KBUILD_ENABLE_EXTRA_GCC_CHECKS)),)
 DTC_FLAGS += -Wno-unit_address_vs_reg \
 	-Wno-simple_bus_reg \
 	-Wno-unit_address_format \
@@ -273,7 +273,7 @@ DTC_FLAGS += -Wno-unit_address_vs_reg \
 	-Wno-pci_device_reg
 endif
 
-ifeq ($(KBUILD_ENABLE_EXTRA_GCC_CHECKS),2)
+ifneq ($(findstring 2,$(KBUILD_ENABLE_EXTRA_GCC_CHECKS)),)
 DTC_FLAGS += -Wnode_name_chars_strict \
 	-Wproperty_name_chars_strict
 endif

scripts/basic/fixdep.c

@@ -104,20 +104,12 @@
 
 #include <sys/types.h>
 #include <sys/stat.h>
-#include <sys/mman.h>
 #include <unistd.h>
 #include <fcntl.h>
 #include <string.h>
 #include <stdlib.h>
 #include <stdio.h>
-#include <limits.h>
 #include <ctype.h>
-#include <arpa/inet.h>
-
-int insert_extra_deps;
-char *target;
-char *depfile;
-char *cmdline;
 
 static void usage(void)
 {
@@ -126,14 +118,6 @@ static void usage(void)
 	exit(1);
 }
 
-/*
- * Print out the commandline prefixed with cmd_<target filename> :=
- */
-static void print_cmdline(void)
-{
-	printf("cmd_%s := %s\n\n", target, cmdline);
-}
-
 /*
  * Print out a dependency path from a symbol name
  */
@@ -155,16 +139,16 @@ static void print_config(const char *m, int slen)
 
 static void do_extra_deps(void)
 {
-	if (insert_extra_deps) {
-		char buf[80];
-		while(fgets(buf, sizeof(buf), stdin)) {
-			int len = strlen(buf);
-			if (len < 2 || buf[len-1] != '\n') {
-				fprintf(stderr, "fixdep: bad data on stdin\n");
-				exit(1);
-			}
-			print_config(buf, len-1);
+	char buf[80];
+
+	while (fgets(buf, sizeof(buf), stdin)) {
+		int len = strlen(buf);
+
+		if (len < 2 || buf[len - 1] != '\n') {
+			fprintf(stderr, "fixdep: bad data on stdin\n");
+			exit(1);
 		}
+		print_config(buf, len - 1);
 	}
 }
 
@@ -235,6 +219,17 @@ static void use_config(const char *m, int slen)
 	print_config(m, slen);
 }
 
+/* test if s ends in sub */
+static int str_ends_with(const char *s, int slen, const char *sub)
+{
+	int sublen = strlen(sub);
+
+	if (sublen > slen)
+		return 0;
+
+	return !memcmp(s + slen - sublen, sub, sublen);
+}
+
 static void parse_config_file(const char *p)
 {
 	const char *q, *r;
@@ -244,7 +239,7 @@ static void parse_config_file(const char *p)
 		q = p;
 		while (*q && (isalnum(*q) || *q == '_'))
 			q++;
-		if (memcmp(q - 7, "_MODULE", 7) == 0)
+		if (str_ends_with(p, q - p, "_MODULE"))
 			r = q - 7;
 		else
 			r = q;
@@ -254,56 +249,46 @@ static void parse_config_file(const char *p)
 	}
 }
 
-/* test if s ends in sub */
-static int strrcmp(const char *s, const char *sub)
-{
-	int slen = strlen(s);
-	int sublen = strlen(sub);
-
-	if (sublen > slen)
-		return 1;
-
-	return memcmp(s + slen - sublen, sub, sublen);
-}
-
-static void do_config_file(const char *filename)
+static void *read_file(const char *filename)
 {
 	struct stat st;
 	int fd;
-	char *map;
+	char *buf;
 
 	fd = open(filename, O_RDONLY);
 	if (fd < 0) {
-		fprintf(stderr, "fixdep: error opening config file: ");
+		fprintf(stderr, "fixdep: error opening file: ");
 		perror(filename);
 		exit(2);
 	}
 	if (fstat(fd, &st) < 0) {
-		fprintf(stderr, "fixdep: error fstat'ing config file: ");
+		fprintf(stderr, "fixdep: error fstat'ing file: ");
 		perror(filename);
 		exit(2);
 	}
-	if (st.st_size == 0) {
-		close(fd);
-		return;
-	}
-	map = malloc(st.st_size + 1);
-	if (!map) {
+	buf = malloc(st.st_size + 1);
+	if (!buf) {
 		perror("fixdep: malloc");
-		close(fd);
-		return;
+		exit(2);
 	}
-	if (read(fd, map, st.st_size) != st.st_size) {
+	if (read(fd, buf, st.st_size) != st.st_size) {
 		perror("fixdep: read");
-		close(fd);
-		return;
+		exit(2);
 	}
-	map[st.st_size] = '\0';
+	buf[st.st_size] = '\0';
 	close(fd);
 
-	parse_config_file(map);
+	return buf;
+}
 
-	free(map);
+/* Ignore certain dependencies */
+static int is_ignored_file(const char *s, int len)
+{
+	return str_ends_with(s, len, "include/generated/autoconf.h") ||
+	       str_ends_with(s, len, "include/generated/autoksyms.h") ||
+	       str_ends_with(s, len, "arch/um/include/uml-config.h") ||
+	       str_ends_with(s, len, "include/linux/kconfig.h") ||
+	       str_ends_with(s, len, ".ver");
 }
 
 /*
@@ -311,71 +296,70 @@ static void do_config_file(const char *filename)
  * assignments are parsed not only by make, but also by the rather simple
  * parser in scripts/mod/sumversion.c.
  */
-static void parse_dep_file(void *map, size_t len)
+static void parse_dep_file(char *m, const char *target, int insert_extra_deps)
 {
-	char *m = map;
-	char *end = m + len;
 	char *p;
-	char s[PATH_MAX];
-	int is_target;
+	int is_last, is_target;
 	int saw_any_target = 0;
 	int is_first_dep = 0;
+	void *buf;
 
-	while (m < end) {
+	while (1) {
 		/* Skip any "white space" */
-		while (m < end && (*m == ' ' || *m == '\\' || *m == '\n'))
+		while (*m == ' ' || *m == '\\' || *m == '\n')
 			m++;
+
+		if (!*m)
+			break;
+
 		/* Find next "white space" */
 		p = m;
-		while (p < end && *p != ' ' && *p != '\\' && *p != '\n')
+		while (*p && *p != ' ' && *p != '\\' && *p != '\n')
 			p++;
+		is_last = (*p == '\0');
 		/* Is the token we found a target name? */
 		is_target = (*(p-1) == ':');
 		/* Don't write any target names into the dependency file */
 		if (is_target) {
 			/* The /next/ file is the first dependency */
 			is_first_dep = 1;
-		} else {
-			/* Save this token/filename */
-			memcpy(s, m, p-m);
-			s[p - m] = 0;
-
-			/* Ignore certain dependencies */
-			if (strrcmp(s, "include/generated/autoconf.h") &&
-			    strrcmp(s, "include/generated/autoksyms.h") &&
-			    strrcmp(s, "arch/um/include/uml-config.h") &&
-			    strrcmp(s, "include/linux/kconfig.h") &&
-			    strrcmp(s, ".ver")) {
+		} else if (!is_ignored_file(m, p - m)) {
+			*p = '\0';
+
+			/*
+			 * Do not list the source file as dependency, so that
+			 * kbuild is not confused if a .c file is rewritten
+			 * into .S or vice versa. Storing it in source_* is
+			 * needed for modpost to compute srcversions.
+			 */
+			if (is_first_dep) {
 				/*
-				 * Do not list the source file as dependency,
-				 * so that kbuild is not confused if a .c file
-				 * is rewritten into .S or vice versa. Storing
-				 * it in source_* is needed for modpost to
-				 * compute srcversions.
+				 * If processing the concatenation of multiple
+				 * dependency files, only process the first
+				 * target name, which will be the original
+				 * source name, and ignore any other target
+				 * names, which will be intermediate temporary
+				 * files.
 				 */
-				if (is_first_dep) {
-					/*
-					 * If processing the concatenation of
-					 * multiple dependency files, only
-					 * process the first target name, which
-					 * will be the original source name,
-					 * and ignore any other target names,
-					 * which will be intermediate temporary
-					 * files.
-					 */
-					if (!saw_any_target) {
-						saw_any_target = 1;
-						printf("source_%s := %s\n\n",
-							target, s);
-						printf("deps_%s := \\\n",
-							target);
-					}
-					is_first_dep = 0;
-				} else
-					printf("  %s \\\n", s);
-				do_config_file(s);
+				if (!saw_any_target) {
+					saw_any_target = 1;
+					printf("source_%s := %s\n\n",
+					       target, m);
+					printf("deps_%s := \\\n", target);
+				}
+				is_first_dep = 0;
+			} else {
+				printf("  %s \\\n", m);
 			}
+
+			buf = read_file(m);
+			parse_config_file(buf);
+			free(buf);
 		}
+
+		if (is_last)
+			break;
+
 		/*
 		 * Start searching for next token immediately after the first
 		 * "whitespace" character that follows this token.
@@ -388,50 +372,19 @@ static void parse_dep_file(void *map, size_t len)
 		exit(1);
 	}
 
-	do_extra_deps();
+	if (insert_extra_deps)
+		do_extra_deps();
 
 	printf("\n%s: $(deps_%s)\n\n", target, target);
 	printf("$(deps_%s):\n", target);
 }
 
-static void print_deps(void)
-{
-	struct stat st;
-	int fd;
-	void *map;
-
-	fd = open(depfile, O_RDONLY);
-	if (fd < 0) {
-		fprintf(stderr, "fixdep: error opening depfile: ");
-		perror(depfile);
-		exit(2);
-	}
-	if (fstat(fd, &st) < 0) {
-		fprintf(stderr, "fixdep: error fstat'ing depfile: ");
-		perror(depfile);
-		exit(2);
-	}
-	if (st.st_size == 0) {
-		fprintf(stderr,"fixdep: %s is empty\n",depfile);
-		close(fd);
-		return;
-	}
-	map = mmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
-	if ((long) map == -1) {
-		perror("fixdep: mmap");
-		close(fd);
-		return;
-	}
-
-	parse_dep_file(map, st.st_size);
-
-	munmap(map, st.st_size);
-
-	close(fd);
-}
-
 int main(int argc, char *argv[])
 {
+	const char *depfile, *target, *cmdline;
+	int insert_extra_deps = 0;
+	void *buf;
+
 	if (argc == 5 && !strcmp(argv[1], "-e")) {
 		insert_extra_deps = 1;
 		argv++;
@@ -442,8 +395,11 @@ int main(int argc, char *argv[])
 	target = argv[2];
 	cmdline = argv[3];
 
-	print_cmdline();
-	print_deps();
+	printf("cmd_%s := %s\n\n", target, cmdline);
+
+	buf = read_file(depfile);
+	parse_dep_file(buf, target, insert_extra_deps);
+	free(buf);
 
 	return 0;
 }