lib9p: idl: Create an 'errno' type

7 files changed, 109 insertions, 81 deletions

diff --git a/lib9p/9p.c b/lib9p/9p.c
index 1caa01a..74a786c 100644
--- a/lib9p/9p.c
+++ b/lib9p/9p.c
@@ -79,7 +79,7 @@ bool lib9p_ctx_has_error(struct lib9p_ctx *ctx) {
 	return ctx->err_msg[0];
 }
 
-int lib9p_error(struct lib9p_ctx *ctx, uint32_t linux_errno, char const *msg) {
+int lib9p_error(struct lib9p_ctx *ctx, lib9p_errno_t linux_errno, char const *msg) {
 	if (lib9p_ctx_has_error(ctx))
 		return -1;
 	strncpy(ctx->err_msg, msg, sizeof(ctx->err_msg));
@@ -94,7 +94,7 @@ int lib9p_error(struct lib9p_ctx *ctx, uint32_t linux_errno, char const *msg) {
 	return -1;
 }
 
-int lib9p_errorf(struct lib9p_ctx *ctx, uint32_t linux_errno, char const *fmt, ...) {
+int lib9p_errorf(struct lib9p_ctx *ctx, lib9p_errno_t linux_errno, char const *fmt, ...) {
 	int n;
 	va_list args;
 
diff --git a/lib9p/9p.generated.c b/lib9p/9p.generated.c
index 567f450..955429e 100644
--- a/lib9p/9p.generated.c
+++ b/lib9p/9p.generated.c
@@ -479,6 +479,12 @@ LM_ALWAYS_INLINE static bool validate_o(struct _validate_ctx *ctx) {
 }
 
 #endif /* CONFIG_9P_ENABLE_9P2000 || CONFIG_9P_ENABLE_9P2000_e || CONFIG_9P_ENABLE_9P2000_p9p || CONFIG_9P_ENABLE_9P2000_u */
+#if CONFIG_9P_ENABLE_9P2000_L || CONFIG_9P_ENABLE_9P2000_u
+LM_ALWAYS_INLINE static bool validate_errno(struct _validate_ctx *ctx) {
+	return validate_4(ctx);
+}
+
+#endif /* CONFIG_9P_ENABLE_9P2000_L || CONFIG_9P_ENABLE_9P2000_u */
 #if CONFIG_9P_ENABLE_9P2000_L
 LM_ALWAYS_INLINE static bool validate_getattr(struct _validate_ctx *ctx) {
 	 if (validate_8(ctx))
@@ -639,22 +645,6 @@ LM_FLATTEN static bool validate_Rwstat(struct _validate_ctx *ctx) {
 
 #endif /* CONFIG_9P_ENABLE_9P2000 || CONFIG_9P_ENABLE_9P2000_e || CONFIG_9P_ENABLE_9P2000_p9p || CONFIG_9P_ENABLE_9P2000_u */
 #if CONFIG_9P_ENABLE_9P2000_L
-LM_FLATTEN static bool validate_Rlerror(struct _validate_ctx *ctx) {
-	uint32_t size;
-	uint8_t typ;
-	uint32_t _size_offset;
-	return false
-	    || (({ _size_offset = ctx->net_offset; validate_4(ctx); }) || ({ size = uint32le_decode(&ctx->net_bytes[ctx->net_offset-4]); false; }))
-	    || (validate_1(ctx) || ({ typ = ctx->net_bytes[ctx->net_offset-1]; false; }))
-	    || validate_tag(ctx)
-	    || validate_4(ctx)
-	    || ({ uint32_t exp = ctx->net_offset - _size_offset; (((uint32_t)size) != exp) &&
-	          lib9p_errorf(ctx->ctx, LINUX_EBADMSG, "size value is wrong (actual:%"PRIu32" != correct:%"PRIu32")", (uint32_t)size, exp); })
-	    || ({ uint8_t exp = 7; (((uint8_t)typ) != exp) &&
-	          lib9p_errorf(ctx->ctx, LINUX_EBADMSG, "typ value is wrong (actual:%"PRIu8" != correct:%"PRIu8")", (uint8_t)typ, exp); })
-	    ;
-}
-
 LM_FLATTEN static bool validate_Rstatfs(struct _validate_ctx *ctx) {
 	uint32_t size;
 	uint8_t typ;
@@ -1108,25 +1098,6 @@ LM_FLATTEN static bool validate_Rversion(struct _validate_ctx *ctx) {
 	    ;
 }
 
-LM_FLATTEN static bool validate_Rerror(struct _validate_ctx *ctx) {
-	uint32_t size;
-	uint8_t typ;
-	uint32_t _size_offset;
-	return false
-	    || (({ _size_offset = ctx->net_offset; validate_4(ctx); }) || ({ size = uint32le_decode(&ctx->net_bytes[ctx->net_offset-4]); false; }))
-	    || (validate_1(ctx) || ({ typ = ctx->net_bytes[ctx->net_offset-1]; false; }))
-	    || validate_tag(ctx)
-	    || validate_s(ctx)
-#if CONFIG_9P_ENABLE_9P2000_u
-	    || ( is_ver(ctx, 9P2000_u) && validate_4(ctx) )
-#endif /* CONFIG_9P_ENABLE_9P2000_u */
-	    || ({ uint32_t exp = ctx->net_offset - _size_offset; (((uint32_t)size) != exp) &&
-	          lib9p_errorf(ctx->ctx, LINUX_EBADMSG, "size value is wrong (actual:%"PRIu32" != correct:%"PRIu32")", (uint32_t)size, exp); })
-	    || ({ uint8_t exp = 107; (((uint8_t)typ) != exp) &&
-	          lib9p_errorf(ctx->ctx, LINUX_EBADMSG, "typ value is wrong (actual:%"PRIu8" != correct:%"PRIu8")", (uint8_t)typ, exp); })
-	    ;
-}
-
 LM_FLATTEN static bool validate_Twalk(struct _validate_ctx *ctx) {
 	uint32_t size;
 	uint8_t typ;
@@ -1553,7 +1524,44 @@ LM_FLATTEN static bool validate_Topenfd(struct _validate_ctx *ctx) {
 }
 
 #endif /* CONFIG_9P_ENABLE_9P2000_p9p */
+#if CONFIG_9P_ENABLE_9P2000 || CONFIG_9P_ENABLE_9P2000_L || CONFIG_9P_ENABLE_9P2000_e || CONFIG_9P_ENABLE_9P2000_p9p || CONFIG_9P_ENABLE_9P2000_u
+LM_FLATTEN static bool validate_Rerror(struct _validate_ctx *ctx) {
+	uint32_t size;
+	uint8_t typ;
+	uint32_t _size_offset;
+	return false
+	    || (({ _size_offset = ctx->net_offset; validate_4(ctx); }) || ({ size = uint32le_decode(&ctx->net_bytes[ctx->net_offset-4]); false; }))
+	    || (validate_1(ctx) || ({ typ = ctx->net_bytes[ctx->net_offset-1]; false; }))
+	    || validate_tag(ctx)
+	    || validate_s(ctx)
+#if CONFIG_9P_ENABLE_9P2000_u
+	    || ( is_ver(ctx, 9P2000_u) && validate_errno(ctx) )
+#endif /* CONFIG_9P_ENABLE_9P2000_u */
+	    || ({ uint32_t exp = ctx->net_offset - _size_offset; (((uint32_t)size) != exp) &&
+	          lib9p_errorf(ctx->ctx, LINUX_EBADMSG, "size value is wrong (actual:%"PRIu32" != correct:%"PRIu32")", (uint32_t)size, exp); })
+	    || ({ uint8_t exp = 107; (((uint8_t)typ) != exp) &&
+	          lib9p_errorf(ctx->ctx, LINUX_EBADMSG, "typ value is wrong (actual:%"PRIu8" != correct:%"PRIu8")", (uint8_t)typ, exp); })
+	    ;
+}
+
+#endif /* CONFIG_9P_ENABLE_9P2000 || CONFIG_9P_ENABLE_9P2000_L || CONFIG_9P_ENABLE_9P2000_e || CONFIG_9P_ENABLE_9P2000_p9p || CONFIG_9P_ENABLE_9P2000_u */
 #if CONFIG_9P_ENABLE_9P2000_L
+LM_FLATTEN static bool validate_Rlerror(struct _validate_ctx *ctx) {
+	uint32_t size;
+	uint8_t typ;
+	uint32_t _size_offset;
+	return false
+	    || (({ _size_offset = ctx->net_offset; validate_4(ctx); }) || ({ size = uint32le_decode(&ctx->net_bytes[ctx->net_offset-4]); false; }))
+	    || (validate_1(ctx) || ({ typ = ctx->net_bytes[ctx->net_offset-1]; false; }))
+	    || validate_tag(ctx)
+	    || validate_errno(ctx)
+	    || ({ uint32_t exp = ctx->net_offset - _size_offset; (((uint32_t)size) != exp) &&
+	          lib9p_errorf(ctx->ctx, LINUX_EBADMSG, "size value is wrong (actual:%"PRIu32" != correct:%"PRIu32")", (uint32_t)size, exp); })
+	    || ({ uint8_t exp = 7; (((uint8_t)typ) != exp) &&
+	          lib9p_errorf(ctx->ctx, LINUX_EBADMSG, "typ value is wrong (actual:%"PRIu8" != correct:%"PRIu8")", (uint8_t)typ, exp); })
+	    ;
+}
+
 LM_FLATTEN static bool validate_Tgetattr(struct _validate_ctx *ctx) {
 	uint32_t size;
 	uint8_t typ;
@@ -2001,6 +2009,12 @@ LM_ALWAYS_INLINE static void unmarshal_o(struct _unmarshal_ctx *ctx, lib9p_o_t *
 }
 
 #endif /* CONFIG_9P_ENABLE_9P2000 || CONFIG_9P_ENABLE_9P2000_e || CONFIG_9P_ENABLE_9P2000_p9p || CONFIG_9P_ENABLE_9P2000_u */
+#if CONFIG_9P_ENABLE_9P2000_L || CONFIG_9P_ENABLE_9P2000_u
+LM_ALWAYS_INLINE static void unmarshal_errno(struct _unmarshal_ctx *ctx, lib9p_errno_t *out) {
+	unmarshal_4(ctx, (uint32_t *)out);
+}
+
+#endif /* CONFIG_9P_ENABLE_9P2000_L || CONFIG_9P_ENABLE_9P2000_u */
 #if CONFIG_9P_ENABLE_9P2000_L
 LM_ALWAYS_INLINE static void unmarshal_getattr(struct _unmarshal_ctx *ctx, lib9p_getattr_t *out) {
 	unmarshal_8(ctx, (uint64_t *)out);
@@ -2082,14 +2096,6 @@ LM_FLATTEN static void unmarshal_Rwstat(struct _unmarshal_ctx *ctx, struct lib9p
 
 #endif /* CONFIG_9P_ENABLE_9P2000 || CONFIG_9P_ENABLE_9P2000_e || CONFIG_9P_ENABLE_9P2000_p9p || CONFIG_9P_ENABLE_9P2000_u */
 #if CONFIG_9P_ENABLE_9P2000_L
-LM_FLATTEN static void unmarshal_Rlerror(struct _unmarshal_ctx *ctx, struct lib9p_msg_Rlerror *out) {
-	memset(out, 0, sizeof(*out));
-	ctx->net_offset += 4;
-	ctx->net_offset += 1;
-	unmarshal_tag(ctx, &out->tag);
-	unmarshal_4(ctx, &out->ecode);
-}
-
 LM_FLATTEN static void unmarshal_Rstatfs(struct _unmarshal_ctx *ctx, struct lib9p_msg_Rstatfs *out) {
 	memset(out, 0, sizeof(*out));
 	ctx->net_offset += 4;
@@ -2324,17 +2330,6 @@ LM_FLATTEN static void unmarshal_Rversion(struct _unmarshal_ctx *ctx, struct lib
 	unmarshal_s(ctx, &out->version);
 }
 
-LM_FLATTEN static void unmarshal_Rerror(struct _unmarshal_ctx *ctx, struct lib9p_msg_Rerror *out) {
-	memset(out, 0, sizeof(*out));
-	ctx->net_offset += 4;
-	ctx->net_offset += 1;
-	unmarshal_tag(ctx, &out->tag);
-	unmarshal_s(ctx, &out->ename);
-#if CONFIG_9P_ENABLE_9P2000_u
-	if ( is_ver(ctx, 9P2000_u) ) unmarshal_4(ctx, &out->errno);
-#endif /* CONFIG_9P_ENABLE_9P2000_u */
-}
-
 LM_FLATTEN static void unmarshal_Twalk(struct _unmarshal_ctx *ctx, struct lib9p_msg_Twalk *out) {
 	memset(out, 0, sizeof(*out));
 	ctx->net_offset += 4;
@@ -2596,7 +2591,28 @@ LM_FLATTEN static void unmarshal_Topenfd(struct _unmarshal_ctx *ctx, struct lib9
 }
 
 #endif /* CONFIG_9P_ENABLE_9P2000_p9p */
+#if CONFIG_9P_ENABLE_9P2000 || CONFIG_9P_ENABLE_9P2000_L || CONFIG_9P_ENABLE_9P2000_e || CONFIG_9P_ENABLE_9P2000_p9p || CONFIG_9P_ENABLE_9P2000_u
+LM_FLATTEN static void unmarshal_Rerror(struct _unmarshal_ctx *ctx, struct lib9p_msg_Rerror *out) {
+	memset(out, 0, sizeof(*out));
+	ctx->net_offset += 4;
+	ctx->net_offset += 1;
+	unmarshal_tag(ctx, &out->tag);
+	unmarshal_s(ctx, &out->ename);
+#if CONFIG_9P_ENABLE_9P2000_u
+	if ( is_ver(ctx, 9P2000_u) ) unmarshal_errno(ctx, &out->errno);
+#endif /* CONFIG_9P_ENABLE_9P2000_u */
+}
+
+#endif /* CONFIG_9P_ENABLE_9P2000 || CONFIG_9P_ENABLE_9P2000_L || CONFIG_9P_ENABLE_9P2000_e || CONFIG_9P_ENABLE_9P2000_p9p || CONFIG_9P_ENABLE_9P2000_u */
 #if CONFIG_9P_ENABLE_9P2000_L
+LM_FLATTEN static void unmarshal_Rlerror(struct _unmarshal_ctx *ctx, struct lib9p_msg_Rlerror *out) {
+	memset(out, 0, sizeof(*out));
+	ctx->net_offset += 4;
+	ctx->net_offset += 1;
+	unmarshal_tag(ctx, &out->tag);
+	unmarshal_errno(ctx, &out->ecode);
+}
+
 LM_FLATTEN static void unmarshal_Tgetattr(struct _unmarshal_ctx *ctx, struct lib9p_msg_Tgetattr *out) {
 	memset(out, 0, sizeof(*out));
 	ctx->net_offset += 4;
diff --git a/lib9p/idl/2005-9P2000.u.9p b/lib9p/idl/2005-9P2000.u.9p
index d96bbce..fefe3e9 100644
--- a/lib9p/idl/2005-9P2000.u.9p
+++ b/lib9p/idl/2005-9P2000.u.9p
@@ -14,6 +14,9 @@ from ./2002-9P2000.9p import *
 num nuid = 4
     "NONUID = ~0"
 
+num errno = 4
+    "NOERROR = 0"
+
 struct stat += "file_extension[s]"
                "file_owner_n_uid[nuid]"
                "file_owner_n_gid[nuid]"
@@ -22,7 +25,7 @@ struct stat += "file_extension[s]"
 msg Tauth   += "n_uid[nuid]"
 msg Tattach += "n_uid[nuid]"
 
-msg Rerror += "errno[4]"
+msg Rerror += "errno[errno]"
 
 bitfield dm += "23=DEVICE"
                "21=NAMEDPIPE"
diff --git a/lib9p/idl/2010-9P2000.L.9p b/lib9p/idl/2010-9P2000.L.9p
index e21d411..9c095ad 100644
--- a/lib9p/idl/2010-9P2000.L.9p
+++ b/lib9p/idl/2010-9P2000.L.9p
@@ -10,7 +10,7 @@ version "9P2000.L"
 from ./2002-9P2000.9p import tag, fid, s, qt, qid
 from ./2002-9P2000.9p import Rerror
 from ./2002-9P2000.9p import Tversion, Rversion, Tflush, Rflush, Twalk, Rwalk, Tread, Rread, Twrite, Rwrite, Tclunk, Rclunk, Tremove, Rremove
-from ./2005-9P2000.u.9p import nuid, Tauth, Rauth, Tattach, Rattach
+from ./2005-9P2000.u.9p import nuid, errno, Tauth, Rauth, Tattach, Rattach
 
 bitfield getattr = 8
          "0=MODE"
@@ -59,7 +59,7 @@ num lock_status = 1
     "GRACE=3"
 
 #msg Tlerror      = "size[4,val=end-&size] typ[1,val=6]  tag[tag] illegal" # analogous to 106/Terror
-msg Rlerror      = "size[4,val=end-&size] typ[1,val=7]  tag[tag] ecode[4]" # analogous to 107/Rerror
+msg Rlerror      = "size[4,val=end-&size] typ[1,val=7]  tag[tag] ecode[errno]" # analogous to 107/Rerror
 msg Tstatfs      = "size[4,val=end-&size] typ[1,val=8]  tag[tag] fid[fid]"
 msg Rstatfs      = "size[4,val=end-&size] typ[1,val=9]  tag[tag] type[4] bsize[4] blocks[8] bfree[8] bavail[8] files[8] ffree[8] fsid[8] namelen[4]"
 msg Tlopen       = "size[4,val=end-&size] typ[1,val=12] tag[tag] fid[fid] flags[4]" # analogous to 112/Topen
diff --git a/lib9p/include/lib9p/9p.generated.h b/lib9p/include/lib9p/9p.generated.h
index f107b1f..9003416 100644
--- a/lib9p/include/lib9p/9p.generated.h
+++ b/lib9p/include/lib9p/9p.generated.h
@@ -261,6 +261,12 @@ typedef uint8_t lib9p_o_t;
 #define   LIB9P_O_FLAG_MASK        ((lib9p_o_t)(0b11111100))
 
 #endif /* CONFIG_9P_ENABLE_9P2000 || CONFIG_9P_ENABLE_9P2000_e || CONFIG_9P_ENABLE_9P2000_p9p || CONFIG_9P_ENABLE_9P2000_u */
+#if CONFIG_9P_ENABLE_9P2000_L || CONFIG_9P_ENABLE_9P2000_u
+/* size = 4 ; max_iov = 1 ; max_copy = 4 */
+typedef uint32_t lib9p_errno_t;
+#define LIB9P_ERRNO_NOERROR ((lib9p_errno_t)UINT32_C(0))
+
+#endif /* CONFIG_9P_ENABLE_9P2000_L || CONFIG_9P_ENABLE_9P2000_u */
 #if CONFIG_9P_ENABLE_9P2000_L
 /* size = 8 ; max_iov = 1 ; max_copy = 8 */
 typedef uint64_t lib9p_getattr_t;
@@ -463,12 +469,6 @@ struct lib9p_msg_Rwstat {
 
 #endif /* CONFIG_9P_ENABLE_9P2000 || CONFIG_9P_ENABLE_9P2000_e || CONFIG_9P_ENABLE_9P2000_p9p || CONFIG_9P_ENABLE_9P2000_u */
 #if CONFIG_9P_ENABLE_9P2000_L
-/* size = 11 ; max_iov = 1 ; max_copy = 11 */
-struct lib9p_msg_Rlerror {
-	lib9p_tag_t   tag;
-	uint32_t      ecode;
-};
-
 /* size = 67 ; max_iov = 1 ; max_copy = 67 */
 struct lib9p_msg_Rstatfs {
 	lib9p_tag_t   tag;
@@ -648,19 +648,6 @@ struct lib9p_msg_Rversion {
 	struct lib9p_s   version;
 };
 
-/* LIB9P_VER_9P2000    : min_size = 9 ; exp_size = 36 ; max_size = 65,544 ; max_iov = 2 ; max_copy = 9 */
-/* LIB9P_VER_9P2000_L  : min_size = 9 ; exp_size = 36 ; max_size = 65,544 ; max_iov = 2 ; max_copy = 9 */
-/* LIB9P_VER_9P2000_e  : min_size = 9 ; exp_size = 36 ; max_size = 65,544 ; max_iov = 2 ; max_copy = 9 */
-/* LIB9P_VER_9P2000_p9p: min_size = 9 ; exp_size = 36 ; max_size = 65,544 ; max_iov = 2 ; max_copy = 9 */
-/* LIB9P_VER_9P2000_u  : min_size = 13 ; exp_size = 40 ; max_size = 65,548 ; max_iov = 3 ; max_copy = 13 */
-struct lib9p_msg_Rerror {
-	lib9p_tag_t      tag;
-	struct lib9p_s   ename;
-#if CONFIG_9P_ENABLE_9P2000_u
-	uint32_t         errno;
-#endif /* CONFIG_9P_ENABLE_9P2000_u */
-};
-
 /* min_size = 17 ; exp_size = 481 ; max_size = 1,048,609 ; max_iov = 32 ; max_copy = 49 */
 struct lib9p_msg_Twalk {
 	lib9p_tag_t      tag;
@@ -878,7 +865,28 @@ struct lib9p_msg_Topenfd {
 };
 
 #endif /* CONFIG_9P_ENABLE_9P2000_p9p */
+#if CONFIG_9P_ENABLE_9P2000 || CONFIG_9P_ENABLE_9P2000_L || CONFIG_9P_ENABLE_9P2000_e || CONFIG_9P_ENABLE_9P2000_p9p || CONFIG_9P_ENABLE_9P2000_u
+/* LIB9P_VER_9P2000    : min_size = 9 ; exp_size = 36 ; max_size = 65,544 ; max_iov = 2 ; max_copy = 9 */
+/* LIB9P_VER_9P2000_L  : min_size = 9 ; exp_size = 36 ; max_size = 65,544 ; max_iov = 2 ; max_copy = 9 */
+/* LIB9P_VER_9P2000_e  : min_size = 9 ; exp_size = 36 ; max_size = 65,544 ; max_iov = 2 ; max_copy = 9 */
+/* LIB9P_VER_9P2000_p9p: min_size = 9 ; exp_size = 36 ; max_size = 65,544 ; max_iov = 2 ; max_copy = 9 */
+/* LIB9P_VER_9P2000_u  : min_size = 13 ; exp_size = 40 ; max_size = 65,548 ; max_iov = 3 ; max_copy = 13 */
+struct lib9p_msg_Rerror {
+	lib9p_tag_t      tag;
+	struct lib9p_s   ename;
+#if CONFIG_9P_ENABLE_9P2000_u
+	lib9p_errno_t    errno;
+#endif /* CONFIG_9P_ENABLE_9P2000_u */
+};
+
+#endif /* CONFIG_9P_ENABLE_9P2000 || CONFIG_9P_ENABLE_9P2000_L || CONFIG_9P_ENABLE_9P2000_e || CONFIG_9P_ENABLE_9P2000_p9p || CONFIG_9P_ENABLE_9P2000_u */
 #if CONFIG_9P_ENABLE_9P2000_L
+/* size = 11 ; max_iov = 1 ; max_copy = 11 */
+struct lib9p_msg_Rlerror {
+	lib9p_tag_t     tag;
+	lib9p_errno_t   ecode;
+};
+
 /* size = 19 ; max_iov = 1 ; max_copy = 19 */
 struct lib9p_msg_Tgetattr {
 	lib9p_tag_t       tag;
diff --git a/lib9p/include/lib9p/9p.h b/lib9p/include/lib9p/9p.h
index 4ecb172..35b7ef2 100644
--- a/lib9p/include/lib9p/9p.h
+++ b/lib9p/include/lib9p/9p.h
@@ -46,7 +46,7 @@ struct lib9p_ctx {
 
 	/* state */
 #ifdef CONFIG_9P_ENABLE_9P2000_u
-	uint32_t                err_num;
+	lib9p_errno_t           err_num;
 #endif
 	[[gnu::nonstring]] char err_msg[CONFIG_9P_MAX_ERR_SIZE];
 };
@@ -56,9 +56,9 @@ void lib9p_ctx_clear_error(struct lib9p_ctx *ctx);
 bool lib9p_ctx_has_error(struct lib9p_ctx *ctx);
 
 /** Write an static error into ctx, return -1.  */
-int lib9p_error(struct lib9p_ctx *ctx, uint32_t linux_errno, char const *msg);
+int lib9p_error(struct lib9p_ctx *ctx, lib9p_errno_t linux_errno, char const *msg);
 /** Write a printf-style error into ctx, return -1.  */
-int lib9p_errorf(struct lib9p_ctx *ctx, uint32_t linux_errno, char const *fmt, ...) [[gnu::format(printf, 3, 4)]];
+int lib9p_errorf(struct lib9p_ctx *ctx, lib9p_errno_t linux_errno, char const *fmt, ...) [[gnu::format(printf, 3, 4)]];
 
 /* main T-message functions ***************************************************/
 
diff --git a/lib9p/tests/test_compile.c b/lib9p/tests/test_compile.c
index 0e33522..d001b2f 100644
--- a/lib9p/tests/test_compile.c
+++ b/lib9p/tests/test_compile.c
@@ -46,6 +46,7 @@ int main(void) {
     x = LIB9P_O_EXEC;
     x = LIB9P_O_MODE_MASK;
     x = LIB9P_O_FLAG_MASK;
+    x = LIB9P_ERRNO_NOERROR;
     x = LIB9P_GETATTR_DATA_VERSION;
     x = LIB9P_GETATTR_GEN;
     x = LIB9P_GETATTR_BTIME;