Re: cyrus-imapd: FTBFS on arm*, i386, mipsel, ppc64el and s390x

[John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>]

Hi Xavier!

On 5/11/20 11:56 PM, Xavier wrote:
> Could someone help us here ? I forwarded this bug to upstream ([1]) but
> didn't receive any response for now.
> 
> (Cc to RFH bug)

The problem here is va_list. On some architectures, the calling convention
doesn't seem to allow comparing va_list against NULL due to the way va_list
is implemented on a particular architecture.

You could maybe add an auxiliary boolean variable to control whether
"va_list args" is empty or not, i.e. something like this:

Index: cyrus-imapd-3.2.0/imap/httpd.c
===================================================================
--- cyrus-imapd-3.2.0.orig/imap/httpd.c
+++ cyrus-imapd-3.2.0/imap/httpd.c
@@ -2350,7 +2350,7 @@ EXPORTED void simple_hdr(struct transact
     simple_hdr(txn, "Access-Control-Expose-Headers", hdr)
 
 static void comma_list_body(struct buf *buf,
-                            const char *vals[], unsigned flags, va_list args)
+                            const char *vals[], unsigned flags, int has_args, va_list args)
 {
     const char *sep = "";
     int i;
@@ -2358,11 +2358,11 @@ static void comma_list_body(struct buf *
     for (i = 0; vals[i]; i++) {
         if (flags & (1 << i)) {
             buf_appendcstr(buf, sep);
-            if (args) buf_vprintf(buf, vals[i], args);
+            if (has_args) buf_vprintf(buf, vals[i], args);
             else buf_appendcstr(buf, vals[i]);
             sep = ", ";
         }
-        else if (args) {
+        else if (has_args) {
             /* discard any unused args */
             vsnprintf(NULL, 0, vals[i], args);
         }
@@ -2377,7 +2377,7 @@ EXPORTED void comma_list_hdr(struct tran
 
     va_start(args, flags);
 
-    comma_list_body(&buf, vals, flags, args);
+    comma_list_body(&buf, vals, flags, 1, args);
 
     va_end(args);
 
@@ -3077,17 +3077,17 @@ EXPORTED void response_header(long code,
     }
     if (code == HTTP_SWITCH_PROT || code == HTTP_UPGRADE) {
         buf_printf(logbuf, "%supgrade=", sep);
-        comma_list_body(logbuf, upgrd_tokens, txn->flags.upgrade, NULL);
+        comma_list_body(logbuf, upgrd_tokens, txn->flags.upgrade, 0, 0);
         sep = "; ";
     }
     if (txn->flags.te) {
         buf_printf(logbuf, "%stx-encoding=", sep);
-        comma_list_body(logbuf, te, txn->flags.te, NULL);
+        comma_list_body(logbuf, te, txn->flags.te, 0, 0);
         sep = "; ";
     }
     if (txn->resp_body.enc.proc) {
         buf_printf(logbuf, "%scnt-encoding=", sep);
-        comma_list_body(logbuf, ce, txn->resp_body.enc.type, NULL);
+        comma_list_body(logbuf, ce, txn->resp_body.enc.type, 0, 0);
         sep = "; ";
     }
     if (txn->location) {

Adrian

-- 
 .''`.  John Paul Adrian Glaubitz
: :' :  Debian Developer - glaubitz@debian.org
`. `'   Freie Universitaet Berlin - glaubitz@physik.fu-berlin.de
  `-    GPG: 62FF 8A75 84E0 2956 9546  0006 7426 3B37 F5B5 F913

Description: Don't try to compare va_list against NULL
Author: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Last-Update: 2020-05-12


Index: cyrus-imapd-3.2.0/imap/httpd.c
===================================================================
--- cyrus-imapd-3.2.0.orig/imap/httpd.c
+++ cyrus-imapd-3.2.0/imap/httpd.c
@@ -2350,7 +2350,7 @@ EXPORTED void simple_hdr(struct transact
     simple_hdr(txn, "Access-Control-Expose-Headers", hdr)
 
 static void comma_list_body(struct buf *buf,
-                            const char *vals[], unsigned flags, va_list args)
+                            const char *vals[], unsigned flags, int has_args, va_list args)
 {
     const char *sep = "";
     int i;
@@ -2358,11 +2358,11 @@ static void comma_list_body(struct buf *
     for (i = 0; vals[i]; i++) {
         if (flags & (1 << i)) {
             buf_appendcstr(buf, sep);
-            if (args) buf_vprintf(buf, vals[i], args);
+            if (has_args) buf_vprintf(buf, vals[i], args);
             else buf_appendcstr(buf, vals[i]);
             sep = ", ";
         }
-        else if (args) {
+        else if (has_args) {
             /* discard any unused args */
             vsnprintf(NULL, 0, vals[i], args);
         }
@@ -2377,7 +2377,7 @@ EXPORTED void comma_list_hdr(struct tran
 
     va_start(args, flags);
 
-    comma_list_body(&buf, vals, flags, args);
+    comma_list_body(&buf, vals, flags, 1, args);
 
     va_end(args);
 
@@ -3077,17 +3077,17 @@ EXPORTED void response_header(long code,
     }
     if (code == HTTP_SWITCH_PROT || code == HTTP_UPGRADE) {
         buf_printf(logbuf, "%supgrade=", sep);
-        comma_list_body(logbuf, upgrd_tokens, txn->flags.upgrade, NULL);
+        comma_list_body(logbuf, upgrd_tokens, txn->flags.upgrade, 0, 0);
         sep = "; ";
     }
     if (txn->flags.te) {
         buf_printf(logbuf, "%stx-encoding=", sep);
-        comma_list_body(logbuf, te, txn->flags.te, NULL);
+        comma_list_body(logbuf, te, txn->flags.te, 0, 0);
         sep = "; ";
     }
     if (txn->resp_body.enc.proc) {
         buf_printf(logbuf, "%scnt-encoding=", sep);
-        comma_list_body(logbuf, ce, txn->resp_body.enc.type, NULL);
+        comma_list_body(logbuf, ce, txn->resp_body.enc.type, 0, 0);
         sep = "; ";
     }
     if (txn->location) {