I cannot test this patch unfortunately, build icedtea-8 fails for me
with


--8<---------------cut here---------------start------------->8---
INFO: ZIP_DEBUGINFO_FILES=1
echo Generating precompiled header precompiled.hpp.gch
Generating precompiled header precompiled.hpp.gch
mkdir -p .
/gnu/store/x3jx25cd3q363mr7nbgzrhrv1vza6cf7-gcc-7.4.0/bin/g++ -DLINUX -D_GNU_SOURCE -DAMD64 -DPRODUCT -I. -I/tmp/guix-build-icedtea-3.7.0.drv-0/icedtea-2.6.13/openjdk/hotspot/src/share/vm/prims -I/tmp/guix-build-icedtea-3.7.0.drv-0/icedtea-2.6.13/openjdk/hotspot/src/share/vm -I/tmp/guix-build-icedtea-3.7.0.drv-0/icedtea-2.6.13/openjdk/hotspot/src/share/vm/precompiled -I/tmp/guix-build-icedtea-3.7.0.drv-0/icedtea-2.6.13/openjdk/hotspot/src/cpu/x86/vm -I/tmp/guix-build-icedtea-3.7.0.drv-0/icedtea-2.6.13/openjdk/hotspot/src/os_cpu/linux_x86/vm -I/tmp/guix-build-icedtea-3.7.0.drv-0/icedtea-2.6.13/openjdk/hotspot/src/os/linux/vm -I/tmp/guix-build-icedtea-3.7.0.drv-0/icedtea-2.6.13/openjdk/hotspot/src/os/posix/vm -I../generated -DHOTSPOT_RELEASE_VERSION="\"25.161-b12\"" -DHOTSPOT_BUILD_TARGET="\"product\"" -DHOTSPOT_BUILD_USER="\"nixbld\"" -DHOTSPOT_LIB_ARCH=\"amd64\" -DHOTSPOT_VM_DISTRO="\"OpenJDK\"" -DDERIVATIVE_ID="\"IcedTea 3.7.0\"" -DDISTRIBUTION_ID="\"Custom build\""  -DTARGET_OS_FAMILY_linux -DTARGET_ARCH_x86 -DTARGET_ARCH_MODEL_x86_64 -DTARGET_OS_ARCH_linux_x86 -DTARGET_OS_ARCH_MODEL_linux_x86_64 -DTARGET_COMPILER_gcc -DCOMPILER2 -DCOMPILER1 -fPIC -fno-rtti -fno-exceptions -D_REENTRANT -fcheck-new -fvisibility=hidden -m64  -pipe -fno-strict-aliasing  -g -fno-omit-frame-pointer -O3  -DVM_LITTLE_ENDIAN -D_LP64=1  -Wpointer-arith -Wsign-compare -Wundef -Wunused-function -Wunused-value   -g -O2 -fno-delete-null-pointer-checks -fno-lifetime-dse -std=gnu++98 -c -MMD -MP -MF ../generated/dependencies/precompiled.hpp.gch.d -fpch-deps -x c++-header /tmp/guix-build-icedtea-3.7.0.drv-0/icedtea-2.6.13/openjdk/hotspot/src/share/vm/precompiled/precompiled.hpp -o precompiled.hpp.gch 
In file included from /tmp/guix-build-icedtea-3.7.0.drv-0/icedtea-2.6.13/openjdk/hotspot/src/share/vm/precompiled/precompiled.hpp:315:0:
/tmp/guix-build-icedtea-3.7.0.drv-0/icedtea-2.6.13/openjdk/hotspot/src/share/vm/gc_implementation/parallelScavenge/parallelScavengeHeap.hpp:250:2: fatal error: can't write PCH file: No space left on device
 };
  ^
compilation terminated.
--8<---------------cut here---------------end--------------->8---

Even though I do have enough space and memory left.
Unsure what's going on.

-- 
Pierre Neidhardt
https://ambrevar.xyz/