[pacman-dev] [PATCH] fix clang -Wformat-nonliteral warnings

[Andrew Gregory]

GCC is smart enough not to issue a warning when calling a printf
function using a va_list; clang is not.  Selectively disable the warning
using pragmas to allow building with warnings using clang.

Signed-off-by: Andrew Gregory <andrew.gregory.8 at gmail.com>
---

Adding a bunch of pragmas doesn't strike me as an ideal solution, but clang's
warning flag documentation is non-existent and I can't find another solution
other than removing -Wformat-nonliteral altogether.

 lib/libalpm/util.c      |  3 +++
 src/pacman/callback.c   |  3 +++
 src/pacman/util.c       | 12 ++++++++++++
 src/util/cleanupdelta.c |  3 +++
 src/util/testdb.c       |  3 +++
 src/util/testpkg.c      |  4 ++++
 6 files changed, 28 insertions(+)

diff --git a/lib/libalpm/util.c b/lib/libalpm/util.c
index f4c33a0..a2f279c 100644
--- a/lib/libalpm/util.c
+++ b/lib/libalpm/util.c
@@ -463,6 +463,8 @@ int _alpm_logaction(alpm_handle_t *handle, const char *prefix,
 		prefix = "UNKNOWN";
 	}
 
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wformat-nonliteral"
 	if(handle->usesyslog) {
 		/* we can't use a va_list more than once, so we need to copy it
 		 * so we can use the original when calling vfprintf below. */
@@ -486,6 +488,7 @@ int _alpm_logaction(alpm_handle_t *handle, const char *prefix,
 		ret = vfprintf(handle->logstream, fmt, args);
 		fflush(handle->logstream);
 	}
+#pragma clang diagnostic pop
 
 	return ret;
 }
diff --git a/src/pacman/callback.c b/src/pacman/callback.c
index edd5b39..16a04f3 100644
--- a/src/pacman/callback.c
+++ b/src/pacman/callback.c
@@ -772,6 +772,8 @@ void cb_log(alpm_loglevel_t level, const char *fmt, va_list args)
 		return;
 	}
 
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wformat-nonliteral"
 	if(on_progress) {
 		char *string = NULL;
 		pm_vasprintf(&string, level, fmt, args);
@@ -781,6 +783,7 @@ void cb_log(alpm_loglevel_t level, const char *fmt, va_list args)
 	} else {
 		pm_vfprintf(stderr, level, fmt, args);
 	}
+#pragma clang diagnostic pop
 }
 
 /* vim: set ts=2 sw=2 noet: */
diff --git a/src/pacman/util.c b/src/pacman/util.c
index 03063fb..da3170a 100644
--- a/src/pacman/util.c
+++ b/src/pacman/util.c
@@ -1460,7 +1460,10 @@ static int question(short preset, char *fmt, va_list args)
 	fflush(stdout);
 	fflush(stderr);
 
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wformat-nonliteral"
 	vfprintf(stream, fmt, args);
+#pragma clang diagnostic pop
 
 	if(preset) {
 		fprintf(stream, " %s ", _("[Y/n]"));
@@ -1526,10 +1529,13 @@ int pm_printf(alpm_loglevel_t level, const char *format, ...)
 	int ret;
 	va_list args;
 
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wformat-nonliteral"
 	/* print the message using va_arg list */
 	va_start(args, format);
 	ret = pm_vfprintf(stderr, level, format, args);
 	va_end(args);
+#pragma clang diagnostic pop
 
 	return ret;
 }
@@ -1539,6 +1545,8 @@ int pm_asprintf(char **string, const char *format, ...)
 	int ret = 0;
 	va_list args;
 
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wformat-nonliteral"
 	/* print the message using va_arg list */
 	va_start(args, format);
 	if(vasprintf(string, format, args) == -1) {
@@ -1546,6 +1554,7 @@ int pm_asprintf(char **string, const char *format, ...)
 		ret = -1;
 	}
 	va_end(args);
+#pragma clang diagnostic pop
 
 	return ret;
 }
@@ -1561,7 +1570,10 @@ int pm_vasprintf(char **string, alpm_loglevel_t level, const char *format, va_li
 	}
 
 	/* print the message using va_arg list */
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wformat-nonliteral"
 	ret = vasprintf(&msg, format, args);
+#pragma clang diagnostic pop
 
 	/* print a prefix to the message */
 	switch(level) {
diff --git a/src/util/cleanupdelta.c b/src/util/cleanupdelta.c
index 144e038..ff17427 100644
--- a/src/util/cleanupdelta.c
+++ b/src/util/cleanupdelta.c
@@ -39,6 +39,8 @@ static void cleanup(int signum)
 
 static void output_cb(alpm_loglevel_t level, const char *fmt, va_list args)
 {
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wformat-nonliteral"
 	if(strlen(fmt)) {
 		switch(level) {
 			case ALPM_LOG_ERROR: printf("error: "); break;
@@ -48,6 +50,7 @@ static void output_cb(alpm_loglevel_t level, const char *fmt, va_list args)
 		}
 		vprintf(fmt, args);
 	}
+#pragma clang diagnostic pop
 }
 
 
diff --git a/src/util/testdb.c b/src/util/testdb.c
index 2017b60..776d73e 100644
--- a/src/util/testdb.c
+++ b/src/util/testdb.c
@@ -42,6 +42,8 @@ static void cleanup(int signum)
 
 static void output_cb(alpm_loglevel_t level, const char *fmt, va_list args)
 {
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wformat-nonliteral"
 	if(strlen(fmt)) {
 		switch(level) {
 			case ALPM_LOG_ERROR: printf("error: "); break;
@@ -50,6 +52,7 @@ static void output_cb(alpm_loglevel_t level, const char *fmt, va_list args)
 		}
 		vprintf(fmt, args);
 	}
+#pragma clang diagnostic pop
 }
 
 static int check_localdb_files(void)
diff --git a/src/util/testpkg.c b/src/util/testpkg.c
index 96400a7..d310628 100644
--- a/src/util/testpkg.c
+++ b/src/util/testpkg.c
@@ -34,7 +34,11 @@ static void output_cb(alpm_loglevel_t level, const char *fmt, va_list args)
 		case ALPM_LOG_WARNING: printf("warning: "); break;
 		default: return; /* skip other messages */
 	}
+
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wformat-nonliteral"
 	vprintf(fmt, args);
+#pragma clang diagnostic pop
 }
 
 int main(int argc, char *argv[])
-- 
1.8.1.3