Allow Empty Format Strings in Error Macro Invocations
`-Wall` implies `-Wformat-zero-length`, which will cause compilation to fail
under `-Werror` when an empty string is passed as the format string to a
`printf`-family function. This commit moves us back to prefixing the provided
format string, which successfully avoids that warning.
However, this removes the failure mode where that `RAWLOG` invocation would
fail to compile when no format string was provided at all (which was desirable
to avoid having code that would successfully compile normally but fail under
`-pedantic`, which *does* require that a non-zero number of args are provided).
So this commit also introduces a function which does nothing at all, but will
fail to compile if not provided with at least one argument, which is a string.
This successfully links the compilability of pedantic and non-pedantic builds.
diff --git a/lib/common/zstd_internal.h b/lib/common/zstd_internal.h
index 05225e3..856ee14 100644
--- a/lib/common/zstd_internal.h
+++ b/lib/common/zstd_internal.h
@@ -53,6 +53,10 @@
#define MIN(a,b) ((a)<(b) ? (a) : (b))
#define MAX(a,b) ((a)>(b) ? (a) : (b))
+static INLINE_KEYWORD UNUSED_ATTR void _force_has_formatting_string(const char *format, ...) {
+ (void)format;
+}
+
/**
* Return the specified error if the condition evaluates to true.
*
@@ -62,8 +66,10 @@
*/
#define RETURN_ERROR_IF(cond, err, ...) \
if (cond) { \
- RAWLOG(3, "%s:%d: ERROR!: check %s failed, returning %s: ", __FILE__, __LINE__, ZSTD_QUOTE(cond), ZSTD_QUOTE(ERROR(err))); \
- RAWLOG(3, __VA_ARGS__); \
+ RAWLOG(3, "%s:%d: ERROR!: check %s failed, returning %s", \
+ __FILE__, __LINE__, ZSTD_QUOTE(cond), ZSTD_QUOTE(ERROR(err))); \
+ _force_has_formatting_string(__VA_ARGS__); \
+ RAWLOG(3, ": " __VA_ARGS__); \
RAWLOG(3, "\n"); \
return ERROR(err); \
}
@@ -75,8 +81,10 @@
*/
#define RETURN_ERROR(err, ...) \
do { \
- RAWLOG(3, "%s:%d: ERROR!: unconditional check failed, returning %s: ", __FILE__, __LINE__, ZSTD_QUOTE(ERROR(err))); \
- RAWLOG(3, __VA_ARGS__); \
+ RAWLOG(3, "%s:%d: ERROR!: unconditional check failed, returning %s", \
+ __FILE__, __LINE__, ZSTD_QUOTE(ERROR(err))); \
+ _force_has_formatting_string(__VA_ARGS__); \
+ RAWLOG(3, ": " __VA_ARGS__); \
RAWLOG(3, "\n"); \
return ERROR(err); \
} while(0);
@@ -90,8 +98,10 @@
do { \
size_t const err_code = (err); \
if (ERR_isError(err_code)) { \
- RAWLOG(3, "%s:%d: ERROR!: forwarding error in %s: %s: ", __FILE__, __LINE__, ZSTD_QUOTE(err), ERR_getErrorName(err_code)); \
- RAWLOG(3, __VA_ARGS__); \
+ RAWLOG(3, "%s:%d: ERROR!: forwarding error in %s: %s", \
+ __FILE__, __LINE__, ZSTD_QUOTE(err), ERR_getErrorName(err_code)); \
+ _force_has_formatting_string(__VA_ARGS__); \
+ RAWLOG(3, ": " __VA_ARGS__); \
RAWLOG(3, "\n"); \
return err_code; \
} \