diff --git a/scripts/Dockerfile-rockylinux-jdk21-plus b/scripts/Dockerfile-rockylinux-jdk21-plus
index 56734b0be..d7fae9c57 100644
--- a/scripts/Dockerfile-rockylinux-jdk21-plus
+++ b/scripts/Dockerfile-rockylinux-jdk21-plus
@@ -53,6 +53,7 @@ RUN dnf -q -y upgrade && dnf -q -y install \
   ctags \
   devscripts-checkbashisms \
   gcc-c++ \
+  gdb \
   python3 \
   python3-distutils-extra \
   ShellCheck \
@@ -61,6 +62,14 @@ RUN dnf -q -y upgrade && dnf -q -y install \
   texlive \
   yamllint
 
+# Valgrind's gdbserver regression tests, run by Fjalar's CI, need gdb (above)
+# and glibc's debugging information.  (On Ubuntu, that is package libc6-dbg.)
+# `dnf debuginfo-install` is in dnf-plugins-core.  It can succeed without
+# installing anything, so check that glibc-debuginfo got installed.
+RUN dnf -q -y config-manager --set-enabled baseos-debuginfo \
+&& dnf -q -y upgrade && dnf -q -y debuginfo-install glibc \
+&& rpm -q glibc-debuginfo
+
 ## Other ways to install gradle:
 ##  * The `dnf` package repository has a very old version of gradle.
 ##  * Need zip to install SDKMAN, need SDKMAN to install gradle.
diff --git a/scripts/Dockerfile-rockylinux-jdk25-plus b/scripts/Dockerfile-rockylinux-jdk25-plus
index e6d38f466..f5d576b49 100644
--- a/scripts/Dockerfile-rockylinux-jdk25-plus
+++ b/scripts/Dockerfile-rockylinux-jdk25-plus
@@ -54,6 +54,7 @@ RUN dnf -q -y upgrade && dnf -q -y install \
   ctags \
   devscripts-checkbashisms \
   gcc-c++ \
+  gdb \
   python3 \
   python3-distutils-extra \
   ShellCheck \
@@ -62,6 +63,14 @@ RUN dnf -q -y upgrade && dnf -q -y install \
   texlive \
   yamllint
 
+# Valgrind's gdbserver regression tests, run by Fjalar's CI, need gdb (above)
+# and glibc's debugging information.  (On Ubuntu, that is package libc6-dbg.)
+# `dnf debuginfo-install` is in dnf-plugins-core.  It can succeed without
+# installing anything, so check that glibc-debuginfo got installed.
+RUN dnf -q -y config-manager --set-enabled baseos-debuginfo \
+&& dnf -q -y upgrade && dnf -q -y debuginfo-install glibc \
+&& rpm -q glibc-debuginfo
+
 ## Other ways to install gradle:
 ##  * The `dnf` package repository has a very old version of gradle.
 ##  * Need zip to install SDKMAN, need SDKMAN to install gradle.
diff --git a/scripts/Dockerfile-rockylinux-jdk27-plus b/scripts/Dockerfile-rockylinux-jdk27-plus
index b2987a34f..1ccc4f718 100644
--- a/scripts/Dockerfile-rockylinux-jdk27-plus
+++ b/scripts/Dockerfile-rockylinux-jdk27-plus
@@ -58,6 +58,7 @@ RUN dnf -q -y upgrade && dnf -q -y install \
   ctags \
   devscripts-checkbashisms \
   gcc-c++ \
+  gdb \
   python3 \
   python3-distutils-extra \
   ShellCheck \
@@ -66,6 +67,14 @@ RUN dnf -q -y upgrade && dnf -q -y install \
   texlive \
   yamllint
 
+# Valgrind's gdbserver regression tests, run by Fjalar's CI, need gdb (above)
+# and glibc's debugging information.  (On Ubuntu, that is package libc6-dbg.)
+# `dnf debuginfo-install` is in dnf-plugins-core.  It can succeed without
+# installing anything, so check that glibc-debuginfo got installed.
+RUN dnf -q -y config-manager --set-enabled baseos-debuginfo \
+&& dnf -q -y upgrade && dnf -q -y debuginfo-install glibc \
+&& rpm -q glibc-debuginfo
+
 ## Other ways to install gradle:
 ##  * The `dnf` package repository has a very old version of gradle.
 ##  * Need zip to install SDKMAN, need SDKMAN to install gradle.
diff --git a/scripts/Dockerfile-rockylinux.m4 b/scripts/Dockerfile-rockylinux.m4
index 82efb31cc..b0d510e98 100644
--- a/scripts/Dockerfile-rockylinux.m4
+++ b/scripts/Dockerfile-rockylinux.m4
@@ -58,6 +58,7 @@ RUN dnf -q -y upgrade && dnf -q -y install \
   ctags \
   devscripts-checkbashisms \
   gcc-c++ \
+  gdb \
   python3 \
   python3-distutils-extra \
   ShellCheck \
@@ -66,6 +67,14 @@ RUN dnf -q -y upgrade && dnf -q -y install \
   texlive \
   yamllint
 
+# Valgrind's gdbserver regression tests, run by Fjalar's CI, need gdb (above)
+# and glibc's debugging information.  (On Ubuntu, that is package libc6-dbg.)
+# `dnf debuginfo-install` is in dnf-plugins-core.  It can succeed without
+# installing anything, so check that glibc-debuginfo got installed.
+RUN dnf -q -y config-manager --set-enabled baseos-debuginfo \
+&& dnf -q -y upgrade && dnf -q -y debuginfo-install glibc \
+&& rpm -q glibc-debuginfo
+
 ## Other ways to install gradle:
 ##  * The `dnf` package repository has a very old version of gradle.
 ##  * Need zip to install SDKMAN, need SDKMAN to install gradle.
diff --git a/scripts/Dockerfile-ubuntu-jdk11-plus b/scripts/Dockerfile-ubuntu-jdk11-plus
index 648a5e9d5..f40bb7009 100644
--- a/scripts/Dockerfile-ubuntu-jdk11-plus
+++ b/scripts/Dockerfile-ubuntu-jdk11-plus
@@ -68,6 +68,7 @@ RUN export DEBIAN_FRONTEND=noninteractive \
 && apt-get -qqy install \
   devscripts \
   g++ \
+  gdb \
   libc6-dbg \
   python3-setuptools \
   shellcheck \
diff --git a/scripts/Dockerfile-ubuntu-jdk17-plus b/scripts/Dockerfile-ubuntu-jdk17-plus
index 2c1d65c63..a371c343c 100644
--- a/scripts/Dockerfile-ubuntu-jdk17-plus
+++ b/scripts/Dockerfile-ubuntu-jdk17-plus
@@ -68,6 +68,7 @@ RUN export DEBIAN_FRONTEND=noninteractive \
 && apt-get -qqy install \
   devscripts \
   g++ \
+  gdb \
   libc6-dbg \
   python3-setuptools \
   shellcheck \
diff --git a/scripts/Dockerfile-ubuntu-jdk21-plus b/scripts/Dockerfile-ubuntu-jdk21-plus
index a99746655..53beb12fa 100644
--- a/scripts/Dockerfile-ubuntu-jdk21-plus
+++ b/scripts/Dockerfile-ubuntu-jdk21-plus
@@ -68,6 +68,7 @@ RUN export DEBIAN_FRONTEND=noninteractive \
 && apt-get -qqy install \
   devscripts \
   g++ \
+  gdb \
   libc6-dbg \
   python3-setuptools \
   shellcheck \
diff --git a/scripts/Dockerfile-ubuntu-jdk25-plus b/scripts/Dockerfile-ubuntu-jdk25-plus
index 6254e5e04..6bda93dae 100644
--- a/scripts/Dockerfile-ubuntu-jdk25-plus
+++ b/scripts/Dockerfile-ubuntu-jdk25-plus
@@ -69,6 +69,7 @@ RUN export DEBIAN_FRONTEND=noninteractive \
 && apt-get -qqy install \
   devscripts \
   g++ \
+  gdb \
   libc6-dbg \
   python3-setuptools \
   shellcheck \
diff --git a/scripts/Dockerfile-ubuntu-jdk27-plus b/scripts/Dockerfile-ubuntu-jdk27-plus
index e9d7ec91d..13775ae48 100644
--- a/scripts/Dockerfile-ubuntu-jdk27-plus
+++ b/scripts/Dockerfile-ubuntu-jdk27-plus
@@ -69,6 +69,7 @@ RUN export DEBIAN_FRONTEND=noninteractive \
 && apt-get -qqy install \
   devscripts \
   g++ \
+  gdb \
   libc6-dbg \
   python3-setuptools \
   shellcheck \
diff --git a/scripts/Dockerfile-ubuntu.m4 b/scripts/Dockerfile-ubuntu.m4
index b0e0b2d2b..e3c872e50 100644
--- a/scripts/Dockerfile-ubuntu.m4
+++ b/scripts/Dockerfile-ubuntu.m4
@@ -71,6 +71,7 @@ RUN export DEBIAN_FRONTEND=noninteractive \
 && apt-get -qqy install \
   devscripts \
   g++ \
+  gdb \
   libc6-dbg \
   python3-setuptools \
   shellcheck \