diff --git a/auto.def b/auto.def
index e5da690c24..1a6bd03614 100644
--- a/auto.def
+++ b/auto.def
@@ -850,6 +850,8 @@ proc sqlite-check-line-editing {} {
         set rlInc "-I${rlInc}"
       }
     }
+  } elseif {"" ne $rlInc && ![string match *-I* $rlInc]} {
+    proj-fatal "Argument to --with-readline-cflag is intended to be CFLAGS and contain -I..."
   }
 
   # If readline.h was found/specified, look for lib(readline|edit)...
diff --git a/manifest b/manifest
index 08feab3ee4..5f72c6369e 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C General\sauto.def\scleanups\sand\sdocs.
-D 2024-10-29T20:27:36.141
+C Try\sto\sdetect\sif\s--with-readline-cflags\sis\spassed\sa\snon-cflags\svalue,\se.g.\sreadline/readline.h,\sand\sfail\sloudly\sif\sit\sis.\sThe\slegacy\sconfigure\saccepted\sthat\sformulation\sbut\ssilently\sdid\snothing\suseful\swith\sit\sand\sthat\sformulation\snow\scauses\sthe\sauto-completion\stest\sto\sfail,\sas\sreported\sin\s[forum:f13b8e8f38402367\s|\sforum\spost\sf13b8e8f38402367].
+D 2024-10-29T23:19:29.053
 F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
 F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
 F LICENSE.md c5b4009dca54d127d2d6033c22fd9cc34f53bedb6ef12c7cbaa468381c74ab28
@@ -13,7 +13,7 @@ F art/icon-80x90.gif 65509ce3e5f86a9cd64fe7fca2d23954199f31fe44c1e09e208c80fb83d
 F art/sqlite370.eps aa97a671332b432a54e1d74ff5e8775be34200c2
 F art/sqlite370.ico af56c1d00fee7cd4753e8631ed60703ed0fc6e90
 F art/sqlite370.jpg d512473dae7e378a67e28ff96a34da7cb331def2
-F auto.def 50cf59530afe1a068fd1a981d5a12461e8acaaeff69778c0909aa1d29f1fea44
+F auto.def b617eeed76cfc37c16462b77cc214646313df96ff904d2328042e496f2b0c9f4
 F autoconf/INSTALL 83e4a25da9fd053c7b3665eaaaf7919707915903
 F autoconf/Makefile.am adedc1324b6a87fdd1265ddd336d2fb7d4f36a0e77b86ea553ae7cc4ea239347
 F autoconf/Makefile.fallback 22fe523eb36dfce31e0f6349f782eb084e86a5620b2b0b4f84a2d6133f53f5ac
@@ -2198,8 +2198,8 @@ F tool/version-info.c 3b36468a90faf1bbd59c65fd0eb66522d9f941eedd364fabccd7227350
 F tool/warnings-clang.sh bbf6a1e685e534c92ec2bfba5b1745f34fb6f0bc2a362850723a9ee87c1b31a7
 F tool/warnings.sh 49a486c5069de041aedcbde4de178293e0463ae9918ecad7539eedf0ec77a139
 F tool/win/sqlite.vsix deb315d026cc8400325c5863eef847784a219a2f
-P 3891669a3fdd71f7095cf464f6e4e2b870d6c23e79b9f796b1125b2040f05519
-R da60f4bccf0dcae6e53b9b5b4cce8fd0
+P e2f41c2540d8ff7686bfe22336598896de9083d139fc5a291c0f19896b9c1d20
+R b6d32adaf9573d4cf76554f18adf8ffd
 U stephan
-Z ef2b5bc13a71a0b0f34c8682ca475280
+Z 0e7364863ba936108ce5c81e5e566b82
 # Remove this line to create a well-formed Fossil manifest.
diff --git a/manifest.uuid b/manifest.uuid
index f4f4c0c131..c40389ade9 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-e2f41c2540d8ff7686bfe22336598896de9083d139fc5a291c0f19896b9c1d20
+c97f34d064c1fc1e6860761a417aaab2a79bd3871bcd1dad1d0d3b6f4b692a1e