diff --git a/ext/misc/strdup.c b/ext/misc/strdup.c
index 52b1cf0c68..9b54cb7fc0 100644
--- a/ext/misc/strdup.c
+++ b/ext/misc/strdup.c
@@ -52,6 +52,14 @@ SQLITE_EXTENSION_INIT1
 #include <string.h>
 #include <stdlib.h>
 
+/*
+** No-op wrapper around free() to work around problems with non-CDECL
+** calling conventions on 32-bit Windows builds.
+*/
+static void strdupFree(void *p){
+  free(p);
+}
+
 /*
 ** Make a copy of a string or BLOB in memory obtained from malloc().
 */
@@ -75,7 +83,7 @@ static void strdupfunc(
       return;
     }
     if( nIn>0 ) memcpy(zOut, zIn, nIn);
-    sqlite3_result_blob(context, zOut, nIn, free);
+    sqlite3_result_blob(context, zOut, nIn, strdupFree);
   }else{
     zIn = (const unsigned char*)sqlite3_value_text(argv[0]);
     if( zIn==0 ) return;
@@ -87,7 +95,7 @@ static void strdupfunc(
     }
     memcpy(zOut, zIn, nIn);
     zOut[nIn] = 0;
-    sqlite3_result_text64(context, (char*)zOut, nIn, free,
+    sqlite3_result_text64(context, (char*)zOut, nIn, strdupFree,
                           SQLITE_UTF8_ZT);
   }
 }
diff --git a/manifest b/manifest
index 1a563e2840..ad301f305c 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Minor\sinternal\sAPI\sdoc\supdate.
-D 2026-09-18T08:00:34.573
+C Improved\ssupport\sfor\sstdcall\son\s32-bit\swindows,\sfor\slegacy.
+D 2026-09-18T15:38:29.278
 F .fossil-settings/binary-glob 61195414528fb3ea9693577e1980230d78a1f8b0a54c78cf1b9b24d0a409ed6a x
 F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
 F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
@@ -406,7 +406,7 @@ F ext/misc/sqlite3_stdio.c a32a0cf53d82ece9d68c9b9fdaad5f0d2bf696529aece1dbf5c01
 F ext/misc/sqlite3_stdio.h 27a4ecea47e61bc9574ccdf2806f468afe23af2f95028c9b689bfa08ab1ce99f
 F ext/misc/stmt.c b090086cd6bd6281c21271d38d576eeffe662f0e6b67536352ce32bbaa438321
 F ext/misc/stmtrand.c 1c7c6a478e9c808d53a2efa9a744c86c265b6b95b4a96964e1b960c7c642ad49
-F ext/misc/strdup.c 028ea3097c7b6bb8cb9f0b7e656e9bafe6c46db76123e9ad86fb3efda629b568
+F ext/misc/strdup.c eaa6592f5d29543eef591e2919d7410363e2b75d720ee7144a8b31590713c491
 F ext/misc/templatevtab.c e76d4cdb73f986c8165c0fe7831f1a94da55d4f1eafcb7d377e1b0b79ee8679a
 F ext/misc/tmstmpvfs.c 8fe8b10e0ac7c46faf491811e21dcb67ccde5cff8f133701121f793d2a7d41e4
 F ext/misc/totype.c ba11aac3c0b52c685bd25aa4e0f80c41c624fb1cc5ab763250e09ddc762bc3a8
@@ -2172,9 +2172,9 @@ F tool/mkopts.tcl 680f785fdb09729fd9ac50632413da4eadbdf9071535e3f26d03795828ab07
 F tool/mkpragmatab.tcl 5615f8ea9ae6990b73da765c5f121117cbc2a5197b65bed25c56f71c7ab2f42a
 F tool/mkshellc.tcl da6918b128e928a8f0d663519e14829153e59465bd5eb596442e99fa10a411b7
 F tool/mksourceid.c 36aa8020014aed0836fd13c51d6dc9219b0df1761d6b5f58ff5b616211b079b9
-F tool/mksqlite3c-noext.tcl 351c55256213154cabb051a3c870ef9f4487de905015141ae50dc7578a901b84
-F tool/mksqlite3c.tcl 7a268139158e5deef27a370bc2f8db6ccf100c1ad7ac5e5b23743c0fd354f609
-F tool/mksqlite3h.tcl ef6831c97e6e638d2324863e8125306baea239b23defd75da77edffa3b620e81
+F tool/mksqlite3c-noext.tcl 2d92e29cf386729d39497972da4b112b89d5642e0ffec1c991099e547d51ccbb
+F tool/mksqlite3c.tcl d592e422865c5e49e15ffea83401ede2912475efb4071127b9c6599d91423a5d
+F tool/mksqlite3h.tcl f8338b62df8a9dd228c09bb3aab8d9888db5efd7bcbf6a7a68d3bff63335de67
 F tool/mksqlite3internalh.tcl 46ef6ed6ccd3c36e23051109dd25085d8edef3887635cea25afa81c4adf4d4db
 F tool/mksrczip.tcl 81efd9974dbb36005383f2cd655520057a2ae5aa85ac2441a80c7c28f803ac52
 F tool/mktoolzip.tcl c9f388b2b0751982aef29a0c1d80f7959dbe38065ebb4421c39844e92622b086
@@ -2221,8 +2221,11 @@ F tool/warnings-clang.sh bbf6a1e685e534c92ec2bfba5b1745f34fb6f0bc2a362850723a9ee
 F tool/warnings.sh a554d13f6e5cf3760f041b87939e3d616ec6961859c3245e8ef701d1eafc2ca2
 F tool/win/sqlite.vsix deb315d026cc8400325c5863eef847784a219a2f
 F tool/winmain.c 00c8fb88e365c9017db14c73d3c78af62194d9644feaf60e220ab0f411f3604c
-P 8c6c586c3e42dd1d0af4f374b01a660bfc6afb47fd3b34cd7ef16c198ec66d0a
-R c7346c8d02684dff19ae7ef694abb44a
-U stephan
-Z 7ed848ea4d0d2b654de2fb86f34c503b
+P 346c56e02c39858b4364e4c8b8e4c88237e64470066ebb2687ae06d2b0e978b8
+R 9163b5cdf32fd4c5523673c92b3ba0b3
+T *branch * windows-stdcall
+T *sym-windows-stdcall *
+T -sym-trunk *
+U drh
+Z 32fb62985c804744162321bb1e2a4e52
 # Remove this line to create a well-formed Fossil manifest.
diff --git a/manifest.tags b/manifest.tags
index bec971799f..c35acce7b7 100644
--- a/manifest.tags
+++ b/manifest.tags
@@ -1,2 +1,2 @@
-branch trunk
-tag trunk
+branch windows-stdcall
+tag windows-stdcall
diff --git a/manifest.uuid b/manifest.uuid
index 290dc517a1..b3ed674abb 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-346c56e02c39858b4364e4c8b8e4c88237e64470066ebb2687ae06d2b0e978b8
+e638307a519c929271682b9d9093e6dbdc90ca9a07d45ca9fc9ee114d6fd02c7
diff --git a/tool/mksqlite3c-noext.tcl b/tool/mksqlite3c-noext.tcl
index 1148b1c0d5..54e6550d5a 100644
--- a/tool/mksqlite3c-noext.tcl
+++ b/tool/mksqlite3c-noext.tcl
@@ -137,6 +137,7 @@ set cdecllist {
   sqlite3_log
   sqlite3_mprintf
   sqlite3_snprintf
+  sqlite3_str_appendf
   sqlite3_test_control
   sqlite3_vtab_config
 }
diff --git a/tool/mksqlite3c.tcl b/tool/mksqlite3c.tcl
index 0c058672f9..fac29638a8 100644
--- a/tool/mksqlite3c.tcl
+++ b/tool/mksqlite3c.tcl
@@ -220,6 +220,7 @@ set cdecllist {
   sqlite3_log
   sqlite3_mprintf
   sqlite3_snprintf
+  sqlite3_str_appendf
   sqlite3_test_control
   sqlite3_vtab_config
 }
diff --git a/tool/mksqlite3h.tcl b/tool/mksqlite3h.tcl
index c661cd7a33..4fcf3551d6 100644
--- a/tool/mksqlite3h.tcl
+++ b/tool/mksqlite3h.tcl
@@ -160,6 +160,7 @@ set cdecllist {
   sqlite3_log
   sqlite3_mprintf
   sqlite3_snprintf
+  sqlite3_str_appendf
   sqlite3_test_control
   sqlite3_vtab_config
 }