diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 95469979..a44ed622 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -26,7 +26,6 @@ jobs:
             # Uses gcc 12.2.0, clang 15.0.7, cmake 3.24.2
             image: "ubuntu:22.04"
             ubuntu: 22
-            CXXFLAGS: -Wno-stringop-overread
           - name: Debian-10
             # Uses gcc 8.3.0, clang 7.0.1, cmake 3.13.4
             image: "debian:buster"
@@ -65,15 +64,12 @@ jobs:
           - name: Debian-12
             # Uses gcc 12.2.0, clang 15.0.6, cmake 3.25.1
             image: "debian:bookworm"
-            CXXFLAGS: -Wno-stringop-overread
           - name: Debian-12
             image: "debian:bookworm"
             cpp_version: c++17
-            CXXFLAGS: -Wno-stringop-overread
           - name: Debian-12
             image: "debian:bookworm"
             cpp_version: c++20
-            CXXFLAGS: -Wno-stringop-overread
           - name: Debian-12
             image: "debian:bookworm"
             c_compiler: clang
@@ -91,7 +87,6 @@ jobs:
           - name: Debian-12
             image: "debian:bookworm"
             build_type: RelWithDebInfo
-            CXXFLAGS: -Wno-stringop-overread
           - name: Debian-12
             image: "debian:bookworm"
             c_compiler: clang
@@ -100,14 +95,12 @@ jobs:
             LDFLAGS: -fsanitize=address,undefined
           - name: Debian-Testing
             image: "debian:testing"
-            CXXFLAGS: -Wno-stringop-overread -Wno-dangling-reference
           - name: Debian-Testing
             image: "debian:testing"
             c_compiler: clang
             cpp_compiler: clang++
           - name: Debian-Experimental
             image: "debian:experimental"
-            CXXFLAGS: -Wno-stringop-overread -Wno-dangling-reference
           - name: Debian-Experimental
             image: "debian:experimental"
             c_compiler: clang
@@ -115,19 +108,16 @@ jobs:
           - name: Fedora-35
             # Uses gcc 11.2.1, clang 12.0.1, cmake 3.20.5
             image: "fedora:35"
-            CXXFLAGS: -Wno-stringop-overread
           - name: Fedora-36
             # Uses gcc 12.2.0, clang 14.0.5, cmake 3.24.2
             image: "fedora:36"
-            CXXFLAGS: -Wno-stringop-overread
           - name: Fedora-37
             # Uses gcc 12.3.1, clang 15.0.7, cmake 3.26.4
             image: "fedora:37"
-            CXXFLAGS: -Wno-stringop-overread
           - name: Fedora-38
             # Uses gcc 13.0.1, clang 16.0.5, cmake 3.26.4
             image: "fedora:38"
-            CXXFLAGS: -Wno-stringop-overread -Wno-dangling-reference
+            CXXFLAGS: -Wno-dangling-reference
     container:
       image: ${{ matrix.image }}
       env:
diff --git a/include/osmium/osm/object.hpp b/include/osmium/osm/object.hpp
index a62c7603..530fffd7 100644
--- a/include/osmium/osm/object.hpp
+++ b/include/osmium/osm/object.hpp
@@ -316,6 +316,9 @@ namespace osmium {
         }
 
         /// Get user name for this object.
+#if defined(__GNUC__) && (__GNUC__ > 11)
+        [[gnu::noipa]] // avoids stringop-overread warning from GNU compiler
+#endif
         const char* user() const noexcept {
             return reinterpret_cast<const char*>(data() + sizeof_object());
         }
diff --git a/include/osmium/osm/tag.hpp b/include/osmium/osm/tag.hpp
index ac2d0f0c..7dd335d5 100644
--- a/include/osmium/osm/tag.hpp
+++ b/include/osmium/osm/tag.hpp
@@ -51,11 +51,15 @@ namespace osmium {
         friend class osmium::memory::CollectionIterator;
 
         static unsigned char* after_null(unsigned char* ptr) noexcept {
-            return reinterpret_cast<unsigned char*>(std::strchr(reinterpret_cast<char*>(ptr), 0) + 1);
+            while (*ptr) { ++ptr; }
+            ++ptr;
+            return ptr;
         }
 
         static const unsigned char* after_null(const unsigned char* ptr) noexcept {
-            return reinterpret_cast<const unsigned char*>(std::strchr(reinterpret_cast<const char*>(ptr), 0) + 1);
+            while (*ptr) { ++ptr; }
+            ++ptr;
+            return ptr;
         }
 
         unsigned char* next() noexcept {
diff --git a/test/t/tags/test_filter.cpp b/test/t/tags/test_filter.cpp
index 07a4454b..6d36180a 100644
--- a/test/t/tags/test_filter.cpp
+++ b/test/t/tags/test_filter.cpp
@@ -30,10 +30,10 @@ void check_filter(const osmium::TagList& tag_list,
     REQUIRE(std::distance(fi_begin, fi_end) == std::count(reference.begin(), reference.end(), true));
 }
 
-const osmium::TagList& make_tag_list(osmium::memory::Buffer& buffer,
+const osmium::TagList* make_tag_list(osmium::memory::Buffer& buffer,
                                      const std::initializer_list<std::pair<const char*, const char*>>& tags) {
     const auto pos = osmium::builder::add_tag_list(buffer, osmium::builder::attr::_tags(tags));
-    return buffer.get<osmium::TagList>(pos);
+    return &buffer.get<osmium::TagList>(pos);
 }