diff --git a/browser/config/mozconfigs/win64/code-coverage b/browser/config/mozconfigs/win64/code-coverage
index 0770c945afa1..d80d2e8bab2a 100644
--- a/browser/config/mozconfigs/win64/code-coverage
+++ b/browser/config/mozconfigs/win64/code-coverage
@@ -25,7 +25,6 @@ if [ -d "$topsrcdir/clang" ]; then
     CLANG_LIB_DIR="$(cd $topsrcdir/clang/lib/clang/* && cd lib/windows && pwd)"
 
     export LIB=$LIB:$CLANG_LIB_DIR
-    mk_export_correct_style LIB
     export LDFLAGS="clang_rt.profile-x86_64.lib"
 fi
 
diff --git a/build/mozconfig.clang-cl b/build/mozconfig.clang-cl
index bcb5398fde67..efaec52e1d95 100644
--- a/build/mozconfig.clang-cl
+++ b/build/mozconfig.clang-cl
@@ -1,12 +1,10 @@
 if test -d "$topsrcdir/clang/bin"; then
     CLANG_DIR=`cd "$topsrcdir/clang/bin" ; pwd`
     export PATH="${CLANG_DIR}:${PATH}"
-    mk_export_correct_style PATH
 
     if $(cd $topsrcdir/clang/lib/clang/* && test -d lib/windows); then
         CLANG_LIB_DIR="$(cd $topsrcdir/clang/lib/clang/* && cd lib/windows && pwd)"
         export LIB=$LIB:$CLANG_LIB_DIR
-        mk_export_correct_style LIB
     fi
 fi
 
diff --git a/build/mozconfig.lld-link b/build/mozconfig.lld-link
index d63405bd3e03..56f0878ec5c1 100644
--- a/build/mozconfig.lld-link
+++ b/build/mozconfig.lld-link
@@ -1,8 +1,6 @@
 if test -d "$topsrcdir/clang/bin"; then
     CLANG_DIR=`cd "$topsrcdir/clang/bin" ; pwd`
     export PATH="${CLANG_DIR}:${PATH}"
-
-    mk_export_correct_style PATH
 fi
 
 export LINKER=lld-link
diff --git a/build/mozconfig.vs-common b/build/mozconfig.vs-common
deleted file mode 100644
index ca5df2f3aa2b..000000000000
--- a/build/mozconfig.vs-common
+++ /dev/null
@@ -1,4 +0,0 @@
-# Pymake needs Windows-style paths. Use cmd.exe to hack around this.
-mk_export_correct_style() {
-  mk_add_options "export $1=$(cmd.exe //c echo %$1%)"
-}
diff --git a/build/win32/mozconfig.vs2017 b/build/win32/mozconfig.vs2017
index 031cb3ad6c27..49e9bbddf359 100644
--- a/build/win32/mozconfig.vs2017
+++ b/build/win32/mozconfig.vs2017
@@ -23,13 +23,3 @@ if [ -d "${VSPATH}" ]; then
 fi
 
 ac_add_options --target=i686-pc-mingw32
-
-. $topsrcdir/build/mozconfig.vs-common
-
-mk_export_correct_style WINDOWSSDKDIR
-mk_export_correct_style WIN32_REDIST_DIR
-mk_export_correct_style WIN_UCRT_REDIST_DIR
-mk_export_correct_style WIN_DIA_SDK_BIN_DIR
-mk_export_correct_style PATH
-mk_export_correct_style INCLUDE
-mk_export_correct_style LIB
diff --git a/build/win64-aarch64/mozconfig.vs2017 b/build/win64-aarch64/mozconfig.vs2017
index 8df80d7d2c4a..7ee2c709a82e 100644
--- a/build/win64-aarch64/mozconfig.vs2017
+++ b/build/win64-aarch64/mozconfig.vs2017
@@ -35,12 +35,3 @@ if [ -d "${VSPATH}" ]; then
     export WIN64_LINK="${VSPATH}/VC/bin/Hostx64/x64/link.exe"
     export WIN64_LIB="${VSPATH}/VC/lib/x64:${VSPATH}/VC/atlmfc/lib/x64:${VSPATH}/SDK/Lib/${win_sdk_version}/ucrt/x64:${VSPATH}/SDK/Lib/${win_sdk_version}/um/x64:${VSPATH}/DIA SDK/lib/amd64"
 fi
-
-. $topsrcdir/build/mozconfig.vs-common
-
-mk_export_correct_style WINDOWSSDKDIR
-mk_export_correct_style WIN32_REDIST_DIR
-mk_export_correct_style WIN_DIA_SDK_BIN_DIR
-mk_export_correct_style PATH
-mk_export_correct_style INCLUDE
-mk_export_correct_style LIB
diff --git a/build/win64/mozconfig.asan b/build/win64/mozconfig.asan
index af6f1817e64e..c0872d2908f7 100644
--- a/build/win64/mozconfig.asan
+++ b/build/win64/mozconfig.asan
@@ -4,7 +4,6 @@ if [ -d "$topsrcdir/clang" ]; then
     CLANG_LIB_DIR="$(cd $topsrcdir/clang/lib/clang/* && cd lib/windows && pwd)"
 
     export LIB=$LIB:$CLANG_LIB_DIR
-    mk_export_correct_style LIB
     export LDFLAGS="clang_rt.asan_dynamic-x86_64.lib clang_rt.asan_dynamic_runtime_thunk-x86_64.lib"
 
     export MOZ_COPY_PDBS=1
@@ -22,6 +21,5 @@ ac_add_options --disable-jemalloc
 ac_add_options --disable-crashreporter
 ac_add_options --disable-profiling
 
-. "$topsrcdir/build/mozconfig.vs-common"
 . "$topsrcdir/build/mozconfig.clang-cl"
 . "$topsrcdir/build/mozconfig.lld-link"
diff --git a/build/win64/mozconfig.vs2017 b/build/win64/mozconfig.vs2017
index 4601f8105a3a..22a9cdf1c4ec 100644
--- a/build/win64/mozconfig.vs2017
+++ b/build/win64/mozconfig.vs2017
@@ -17,13 +17,3 @@ if [ -d "${VSPATH}" ]; then
     export INCLUDE="${VSPATH}/VC/include:${VSPATH}/VC/atlmfc/include:${VSPATH}/SDK/Include/${win_sdk_version}/ucrt:${VSPATH}/SDK/Include/${win_sdk_version}/shared:${VSPATH}/SDK/Include/${win_sdk_version}/um:${VSPATH}/SDK/Include/${win_sdk_version}/winrt:${VSPATH}/DIA SDK/include"
     export LIB="${VSPATH}/VC/lib/x64:${VSPATH}/VC/atlmfc/lib/x64:${VSPATH}/SDK/Lib/${win_sdk_version}/ucrt/x64:${VSPATH}/SDK/Lib/${win_sdk_version}/um/x64:${VSPATH}/DIA SDK/lib/amd64"
 fi
-
-. $topsrcdir/build/mozconfig.vs-common
-
-mk_export_correct_style WINDOWSSDKDIR
-mk_export_correct_style WIN32_REDIST_DIR
-mk_export_correct_style WIN_UCRT_REDIST_DIR
-mk_export_correct_style WIN_DIA_SDK_BIN_DIR
-mk_export_correct_style PATH
-mk_export_correct_style INCLUDE
-mk_export_correct_style LIB
diff --git a/js/src/devtools/automation/winbuildenv.sh b/js/src/devtools/automation/winbuildenv.sh
index 4dd358177fb9..86b98a4eca70 100644
--- a/js/src/devtools/automation/winbuildenv.sh
+++ b/js/src/devtools/automation/winbuildenv.sh
@@ -1,8 +1,5 @@
-# We will be sourcing mozconfig files, which end up calling mk_add_options with
-# various settings. We only need the variable settings they create along the
-# way. Print them out, to be sucked up when running this file.
-mk_add_options() {
-  echo "$@"
+mk_export_correct_style() {
+  echo "export $1=$(cmd.exe //c echo %$1%)"
 }
 
 topsrcdir="$SOURCE"
@@ -28,6 +25,10 @@ fi
 mk_export_correct_style CC
 mk_export_correct_style CXX
 mk_export_correct_style LINKER
+mk_export_correct_style WINDOWSSDKDIR
+mk_export_correct_style PATH
+mk_export_correct_style INCLUDE
+mk_export_correct_style LIB
 
 # PATH also needs to point to mozmake.exe, which can come from either
 # newer mozilla-build or tooltool.