diff --git a/.github/workflows/linux.yml b/.github/workflows/linux.yml
index 77bd2cf63862ee..bbcee4a42aa76a 100644
--- a/.github/workflows/linux.yml
+++ b/.github/workflows/linux.yml
@@ -119,7 +119,7 @@ jobs:
           - name: openssl3-O3
             install_packages: zlib1g-dev valgrind
             install_steps: gcc-11 openssl3
-            configure: CPPFLAGS=-DCURL_WARN_SIGN_CONVERSION CFLAGS=-O3 LDFLAGS="-Wl,-rpath,$HOME/openssl3/lib" --with-openssl=$HOME/openssl3 --enable-debug --enable-websockets
+            configure: CFLAGS=-O3 LDFLAGS="-Wl,-rpath,$HOME/openssl3/lib" --with-openssl=$HOME/openssl3 --enable-debug --enable-websockets
             singleuse: --unit
 
           - name: openssl3-clang
diff --git a/lib/curl_setup.h b/lib/curl_setup.h
index 0fcb2bded3431d..8fbf01cc839c10 100644
--- a/lib/curl_setup.h
+++ b/lib/curl_setup.h
@@ -28,13 +28,6 @@
 #define CURL_NO_OLDIES
 #endif
 
-/* FIXME: Delete this once the warnings have been fixed. */
-#if !defined(CURL_WARN_SIGN_CONVERSION)
-#ifdef __GNUC__
-#pragma GCC diagnostic ignored "-Wsign-conversion"
-#endif
-#endif
-
 /* Set default _WIN32_WINNT */
 #ifdef __MINGW32__
 #include <_mingw.h>