diff --git a/pycheribuild/projects/cross/gdb.py b/pycheribuild/projects/cross/gdb.py
index 3120f47f4..a8491136b 100644
--- a/pycheribuild/projects/cross/gdb.py
+++ b/pycheribuild/projects/cross/gdb.py
@@ -42,6 +42,7 @@
     MakeCommandKind,
 )
 from .gmp import BuildGmp
+from .mpfr import BuildMpfr
 from ..project import ComputedDefaultValue
 from ...utils import OSInfo
 
@@ -75,7 +76,7 @@ def dependencies(cls, config: CheriConfig) -> "tuple[str, ...]":
         deps = super().dependencies(config)
         # For the native and native-hybrid builds gmp must be installed via ports.
         if not cls.get_crosscompile_target().is_native():
-            deps += ("gmp",)
+            deps += ("gmp", "mpfr")
         return deps
 
     @classmethod
@@ -93,6 +94,7 @@ def check_system_dependencies(self) -> None:
         self.check_required_system_tool("makeinfo", default="texinfo")
         if self.compiling_for_host() and self.target_info.is_cheribsd():
             self.check_required_pkg_config("gmp", freebsd="gmp")
+            self.check_required_pkg_config("mpfr", freebsd="mpfr")
             self.check_required_pkg_config("expat", freebsd="expat")
 
     def __init__(self, *args, **kwargs):
@@ -169,6 +171,7 @@ def setup(self) -> None:
                                               MAKEINFO="/bin/false",
                                               )
             self.configure_args.append("--with-gmp=" + str(BuildGmp.get_install_dir(self)))
+            self.configure_args.append("--with-mpfr=" + str(BuildMpfr.get_install_dir(self)))
             # GDB > 12 only uses --with-gmp
             self.configure_args.append("--with-libgmp-prefix=" + str(BuildGmp.get_install_dir(self)))
             # Autoconf stupidly decides which to use based on file existence
diff --git a/tests/test_argument_parsing.py b/tests/test_argument_parsing.py
index 7c5efbc35..6732b684b 100644
--- a/tests/test_argument_parsing.py
+++ b/tests/test_argument_parsing.py
@@ -127,6 +127,7 @@ def test_skip_update():
                 "llvm-native",
                 "cheribsd-riscv64-purecap",
                 "gmp-riscv64-hybrid-for-purecap-rootfs",
+                "mpfr-riscv64-hybrid-for-purecap-rootfs",
                 "gdb-riscv64-hybrid-for-purecap-rootfs",
                 "bbl-baremetal-riscv64-purecap",
                 "disk-image-riscv64-purecap",
diff --git a/tests/test_target_order.py b/tests/test_target_order.py
index a59251170..11e537caa 100644
--- a/tests/test_target_order.py
+++ b/tests/test_target_order.py
@@ -187,6 +187,7 @@ def test_build_and_run(target_name: str, expected_list: "list[str]"):
                 "morello-llvm-native",
                 "cheribsd-morello-hybrid",
                 "gmp-morello-hybrid",
+                "mpfr-morello-hybrid",
                 "gdb-morello-hybrid",
                 "disk-image-morello-hybrid",
             ],
@@ -199,6 +200,7 @@ def test_build_and_run(target_name: str, expected_list: "list[str]"):
                 "morello-llvm-native",
                 "cheribsd-morello-purecap",
                 "gmp-morello-hybrid-for-purecap-rootfs",
+                "mpfr-morello-hybrid-for-purecap-rootfs",
                 "gdb-morello-hybrid-for-purecap-rootfs",
                 "disk-image-morello-purecap",
             ],
@@ -216,6 +218,7 @@ def test_build_and_run(target_name: str, expected_list: "list[str]"):
                 "llvm-native",
                 "cheribsd-riscv64-hybrid",
                 "gmp-riscv64-hybrid",
+                "mpfr-riscv64-hybrid",
                 "gdb-riscv64-hybrid",
                 "bbl-baremetal-riscv64-purecap",
                 "disk-image-riscv64-hybrid",
@@ -229,6 +232,7 @@ def test_build_and_run(target_name: str, expected_list: "list[str]"):
                 "llvm-native",
                 "cheribsd-riscv64-purecap",
                 "gmp-riscv64-hybrid-for-purecap-rootfs",
+                "mpfr-riscv64-hybrid-for-purecap-rootfs",
                 "gdb-riscv64-hybrid-for-purecap-rootfs",
                 "bbl-baremetal-riscv64-purecap",
                 "disk-image-riscv64-purecap",
@@ -237,12 +241,12 @@ def test_build_and_run(target_name: str, expected_list: "list[str]"):
         pytest.param(
             "run-aarch64",
             True,
-            ["qemu", "llvm-native", "cheribsd-aarch64", "gmp-aarch64", "gdb-aarch64", "disk-image-aarch64"],
+            ["qemu", "llvm-native", "cheribsd-aarch64", "gmp-aarch64", "mpfr-aarch64", "gdb-aarch64", "disk-image-aarch64"],
         ),
         pytest.param(
             "run-amd64",
             True,
-            ["qemu", "llvm-native", "cheribsd-amd64", "gmp-amd64", "gdb-amd64", "disk-image-amd64"],
+            ["qemu", "llvm-native", "cheribsd-amd64", "gmp-amd64", "mpfr-amd64", "gdb-amd64", "disk-image-amd64"],
         ),
         # Morello code won't run on QEMU (yet)
         pytest.param(
@@ -253,6 +257,7 @@ def test_build_and_run(target_name: str, expected_list: "list[str]"):
                 "morello-llvm-native",
                 "cheribsd-morello-hybrid",
                 "gmp-morello-hybrid",
+                "mpfr-morello-hybrid",
                 "gdb-morello-hybrid",
                 "morello-firmware",
                 "disk-image-morello-hybrid",
@@ -266,6 +271,7 @@ def test_build_and_run(target_name: str, expected_list: "list[str]"):
                 "morello-llvm-native",
                 "cheribsd-morello-purecap",
                 "gmp-morello-hybrid-for-purecap-rootfs",
+                "mpfr-morello-hybrid-for-purecap-rootfs",
                 "gdb-morello-hybrid-for-purecap-rootfs",
                 "morello-firmware",
                 "disk-image-morello-purecap",
@@ -532,6 +538,7 @@ def test_riscv():
         "llvm-native",
         "cheribsd-riscv64",
         "gmp-riscv64",
+        "mpfr-riscv64",
         "gdb-riscv64",
         "disk-image-riscv64",
     ]
@@ -540,6 +547,7 @@ def test_riscv():
         "llvm-native",
         "cheribsd-riscv64",
         "gmp-riscv64",
+        "mpfr-riscv64",
         "gdb-riscv64",
         "disk-image-riscv64",
         "run-riscv64",