diff --git a/core/gcc/build b/core/gcc/build
index ed067649..6fadcf91 100755
--- a/core/gcc/build
+++ b/core/gcc/build
@@ -1,14 +1,10 @@
 #!/bin/sh -e
 
-# Make sure gmp is built with generic options.
-cp gcc/gmp/configfsf.guess gcc/gmp/config.guess
-cp gcc/gmp/configfsf.sub   gcc/gmp/config.sub
-
 # Use lib not lib64 by default.
-sed '/m64=/s/lib64/lib/' gcc/gcc/config/i386/t-linux64 > _
-mv -f _ gcc/gcc/config/i386/t-linux64
-sed 's/lib64/lib/' gcc/gcc/config/i386/linux64.h > _
-mv -f _ gcc/gcc/config/i386/linux64.h
+sed '/m64=/s/lib64/lib/' gcc/config/i386/t-linux64 > _
+mv -f _ gcc/config/i386/t-linux64
+sed 's/lib64/lib/' gcc/config/i386/linux64.h > _
+mv -f _ gcc/config/i386/linux64.h
 
 # Build must happen outside of gcc source.
 mkdir -p gcc-build
@@ -23,7 +19,7 @@ case $2 in "${gcc_version%%.*}"*)
     bootstrap=--disable-bootstrap
 esac
 
-../gcc/configure \
+../configure \
     libat_cv_have_ifunc=no \
     --prefix=/usr \
     --libexecdir=/usr/lib \
diff --git a/core/gcc/checksums b/core/gcc/checksums
index 3a59d5aa..c35c9496 100644
--- a/core/gcc/checksums
+++ b/core/gcc/checksums
@@ -1,5 +1,2 @@
 e549cf9cf3594a00e27b6589d4322d70e0720cdd213f39beb4181e06926230ff
-fd4829912cddd12f84181c3451cc752be224643e87fac497b69edddadc49b4f2
-0c98a3f1732ff6ca4ea690552079da9c597872d30e96ec28414ee23c95558a7f
-17503d2c395dfcf106b622dc142683c1199431d095367c6aacba6eec30340459
 765614b3396d70bca3fa0ae4a813632486c6dca320e2bd13c8c39dca52be4a4c
diff --git a/core/gcc/depends b/core/gcc/depends
index ca8b7e57..319f2760 100644
--- a/core/gcc/depends
+++ b/core/gcc/depends
@@ -1,4 +1,7 @@
 binutils
 bison  make
 flex   make
+gmp
+libmpc
+mpfr
 zlib
diff --git a/core/gcc/sources b/core/gcc/sources
index 73217e3c..752635cd 100644
--- a/core/gcc/sources
+++ b/core/gcc/sources
@@ -1,5 +1,2 @@
-https://gcc.gnu.org/pub/gcc/releases/gcc-VERSION/gcc-VERSION.tar.xz gcc
-https://ftp.gnu.org/gnu/gmp/gmp-6.2.1.tar.xz gcc/gmp
-https://ftp.gnu.org/gnu/mpfr/mpfr-4.1.0.tar.xz gcc/mpfr
-https://ftp.gnu.org/gnu/mpc/mpc-1.2.1.tar.gz gcc/mpc
+https://gcc.gnu.org/pub/gcc/releases/gcc-VERSION/gcc-VERSION.tar.xz
 files/c99
diff --git a/core/gcc/version b/core/gcc/version
index 17a9395a..243af9ea 100644
--- a/core/gcc/version
+++ b/core/gcc/version
@@ -1 +1 @@
-12.2.0 1
+12.2.0 2
diff --git a/core/gmp/build b/core/gmp/build
new file mode 100755
index 00000000..412be89a
--- /dev/null
+++ b/core/gmp/build
@@ -0,0 +1,11 @@
+#!/bin/sh -e
+
+./configure \
+    --prefix=/usr \
+    --localstatedir=/var/state/gmp \
+    --enable-cxx \
+    --enable-fat \
+    --with-pic
+
+make
+make DESTDIR="$1" install
diff --git a/core/gmp/checksums b/core/gmp/checksums
new file mode 100644
index 00000000..1335f732
--- /dev/null
+++ b/core/gmp/checksums
@@ -0,0 +1 @@
+fd4829912cddd12f84181c3451cc752be224643e87fac497b69edddadc49b4f2
diff --git a/core/gmp/depends b/core/gmp/depends
new file mode 100644
index 00000000..e8fb4a13
--- /dev/null
+++ b/core/gmp/depends
@@ -0,0 +1 @@
+m4 make
diff --git a/core/gmp/sources b/core/gmp/sources
new file mode 100644
index 00000000..ed0d5312
--- /dev/null
+++ b/core/gmp/sources
@@ -0,0 +1 @@
+https://gmplib.org/download/gmp/gmp-VERSION.tar.xz
diff --git a/core/gmp/version b/core/gmp/version
new file mode 100644
index 00000000..eeb874a0
--- /dev/null
+++ b/core/gmp/version
@@ -0,0 +1 @@
+6.2.1 1
diff --git a/core/libmpc/build b/core/libmpc/build
new file mode 100755
index 00000000..9e85cfce
--- /dev/null
+++ b/core/libmpc/build
@@ -0,0 +1,8 @@
+#!/bin/sh -e
+
+./configure \
+    --prefix=/usr \
+    --enable-shared
+
+make
+make DESTDIR="$1" install
diff --git a/core/libmpc/checksums b/core/libmpc/checksums
new file mode 100644
index 00000000..0a104ca5
--- /dev/null
+++ b/core/libmpc/checksums
@@ -0,0 +1 @@
+17503d2c395dfcf106b622dc142683c1199431d095367c6aacba6eec30340459
diff --git a/core/libmpc/depends b/core/libmpc/depends
new file mode 100644
index 00000000..5bcf2cdf
--- /dev/null
+++ b/core/libmpc/depends
@@ -0,0 +1 @@
+mpfr
diff --git a/core/libmpc/sources b/core/libmpc/sources
new file mode 100644
index 00000000..da39f4e9
--- /dev/null
+++ b/core/libmpc/sources
@@ -0,0 +1 @@
+https://ftp.gnu.org/gnu/mpc/mpc-VERSION.tar.gz
diff --git a/core/libmpc/version b/core/libmpc/version
new file mode 100644
index 00000000..cd3d02bc
--- /dev/null
+++ b/core/libmpc/version
@@ -0,0 +1 @@
+1.2.1 1
diff --git a/core/mpfr/build b/core/mpfr/build
new file mode 100755
index 00000000..6f0a87ab
--- /dev/null
+++ b/core/mpfr/build
@@ -0,0 +1,9 @@
+#!/bin/sh -e
+
+./configure \
+    --prefix=/usr \
+    --enable-shared \
+    --enable-thread-safe
+
+make
+make DESTDIR="$1" install
diff --git a/core/mpfr/checksums b/core/mpfr/checksums
new file mode 100644
index 00000000..178d38c8
--- /dev/null
+++ b/core/mpfr/checksums
@@ -0,0 +1 @@
+0c98a3f1732ff6ca4ea690552079da9c597872d30e96ec28414ee23c95558a7f
diff --git a/core/mpfr/depends b/core/mpfr/depends
new file mode 100644
index 00000000..a0a04787
--- /dev/null
+++ b/core/mpfr/depends
@@ -0,0 +1 @@
+gmp
diff --git a/core/mpfr/sources b/core/mpfr/sources
new file mode 100644
index 00000000..4ef0c368
--- /dev/null
+++ b/core/mpfr/sources
@@ -0,0 +1 @@
+https://www.mpfr.org/mpfr-current/mpfr-VERSION.tar.xz
diff --git a/core/mpfr/version b/core/mpfr/version
new file mode 100644
index 00000000..1bc2766f
--- /dev/null
+++ b/core/mpfr/version
@@ -0,0 +1 @@
+4.1.0 1