diff --git a/eng/common/native/init-compiler.sh b/eng/common/native/init-compiler.sh
index e361e03fabdd2e..6d7ba15e5f2b5d 100644
--- a/eng/common/native/init-compiler.sh
+++ b/eng/common/native/init-compiler.sh
@@ -2,25 +2,45 @@
 #
 # This file detects the C/C++ compiler and exports it to the CC/CXX environment variables
 #
-# NOTE: some scripts source this file and rely on stdout being empty, make sure to not output anything here! 
+# NOTE: some scripts source this file and rely on stdout being empty, make sure to not output anything here!
 
 if [[ "$#" -lt 3 ]]; then
   echo "Usage..."
-  echo "init-compiler.sh <script directory> <Architecture> <compiler> <compiler major version> <compiler minor version>"
+  echo "init-compiler.sh <script directory> <Architecture> <compiler>"
   echo "Specify the script directory."
   echo "Specify the target architecture."
   echo "Specify the name of compiler (clang or gcc)."
-  echo "Specify the major version of compiler."
-  echo "Specify the minor version of compiler."
   exit 1
 fi
 
 nativescriptroot="$1"
 build_arch="$2"
 compiler="$3"
+
+case "$compiler" in
+    clang*|-clang*|--clang*)
+        # clangx.y or clang-x.y
+        version="$(echo "$compiler" | tr -d '[:alpha:]-=')"
+        parts=(${version//./ })
+        majorVersion="${parts[0]}"
+        minorVersion="${parts[1]}"
+        if [[ -z "$minorVersion" && "$majorVersion" -le 6 ]]; then
+            minorVersion=0;
+        fi
+        compiler=clang
+        ;;
+
+    gcc*|-gcc*|--gcc*)
+        # gccx.y or gcc-x.y
+        version="$(echo "$compiler" | tr -d '[:alpha:]-=')"
+        parts=(${version//./ })
+        majorVersion="${parts[0]}"
+        minorVersion="${parts[1]}"
+        compiler=gcc
+        ;;
+esac
+
 cxxCompiler="$compiler++"
-majorVersion="$4"
-minorVersion="$5"
 
 . "$nativescriptroot"/../pipeline-logging-functions.sh
 
diff --git a/eng/native/build-commons.sh b/eng/native/build-commons.sh
index 4aebd45649a04c..8f1a746752a347 100755
--- a/eng/native/build-commons.sh
+++ b/eng/native/build-commons.sh
@@ -117,7 +117,7 @@ build_native()
             scan_build=scan-build
         fi
 
-        nextCommand="\"$__RepoRootDir/eng/native/gen-buildsys.sh\" \"$cmakeDir\" \"$intermediatesDir\" $platformArch $__Compiler \"$__CompilerMajorVersion\" \"$__CompilerMinorVersion\" $__BuildType \"$generator\" $scan_build $cmakeArgs"
+        nextCommand="\"$__RepoRootDir/eng/native/gen-buildsys.sh\" \"$cmakeDir\" \"$intermediatesDir\" $platformArch $__Compiler $__BuildType \"$generator\" $scan_build $cmakeArgs"
         echo "Invoking $nextCommand"
         eval $nextCommand
 
@@ -304,15 +304,7 @@ while :; do
             ;;
 
         clang*|-clang*)
-                __Compiler=clang
-                # clangx.y or clang-x.y
-                version="$(echo "$lowerI" | tr -d '[:alpha:]-=')"
-                parts=(${version//./ })
-                __CompilerMajorVersion="${parts[0]}"
-                __CompilerMinorVersion="${parts[1]}"
-                if [[ -z "$__CompilerMinorVersion" && "$__CompilerMajorVersion" -le 6 ]]; then
-                    __CompilerMinorVersion=0;
-                fi
+            __Compiler="$lowerI"
             ;;
 
         cmakeargs|-cmakeargs)
@@ -340,12 +332,7 @@ while :; do
             ;;
 
         gcc*|-gcc*)
-                __Compiler=gcc
-                # gccx.y or gcc-x.y
-                version="$(echo "$lowerI" | tr -d '[:alpha:]-=')"
-                parts=(${version//./ })
-                __CompilerMajorVersion="${parts[0]}"
-                __CompilerMinorVersion="${parts[1]}"
+            __Compiler="$lowerI"
             ;;
 
         keepnativesymbols|-keepnativesymbols)
diff --git a/eng/native/gen-buildsys.sh b/eng/native/gen-buildsys.sh
index 730d4dcefa7b2d..550613b16341b5 100755
--- a/eng/native/gen-buildsys.sh
+++ b/eng/native/gen-buildsys.sh
@@ -7,13 +7,11 @@ scriptroot="$( cd -P "$( dirname "$0" )" && pwd )"
 
 if [[ "$#" -lt 4 ]]; then
   echo "Usage..."
-  echo "gen-buildsys.sh <path to top level CMakeLists.txt> <path to intermediate directory> <Architecture> <compiler> <compiler major version> <compiler minor version> [build flavor] [ninja] [scan-build] [cmakeargs]"
+  echo "gen-buildsys.sh <path to top level CMakeLists.txt> <path to intermediate directory> <Architecture> <compiler> [build flavor] [ninja] [scan-build] [cmakeargs]"
   echo "Specify the path to the top level CMake file."
   echo "Specify the path that the build system files are generated in."
   echo "Specify the target architecture."
   echo "Specify the name of compiler (clang or gcc)."
-  echo "Specify the major version of compiler."
-  echo "Specify the minor version of compiler."
   echo "Optionally specify the build configuration (flavor.) Defaults to DEBUG."
   echo "Optionally specify 'scan-build' to enable build with clang static analyzer."
   echo "Use the Ninja generator instead of the Unix Makefiles generator."
@@ -23,12 +21,10 @@ fi
 
 build_arch="$3"
 compiler="$4"
-majorVersion="$5"
-minorVersion="$6"
 
 if [[ "$compiler" != "default" ]]; then
     nativescriptroot="$( cd -P "$scriptroot/../common/native" && pwd )"
-    source "$nativescriptroot/init-compiler.sh" "$nativescriptroot" "$build_arch" "$compiler" "$majorVersion" "$minorVersion"
+    source "$nativescriptroot/init-compiler.sh" "$nativescriptroot" "$build_arch" "$compiler"
 
     CCC_CC="$CC"
     CCC_CXX="$CXX"
@@ -43,7 +39,7 @@ scan_build=OFF
 generator="Unix Makefiles"
 __UnprocessedCMakeArgs=""
 
-for i in "${@:7}"; do
+for i in "${@:5}"; do
     upperI="$(echo "$i" | tr "[:lower:]" "[:upper:]")"
     case "$upperI" in
       # Possible build types are DEBUG, CHECKED, RELEASE, RELWITHDEBINFO.
diff --git a/src/coreclr/build-runtime.sh b/src/coreclr/build-runtime.sh
index b70cf1eab3c45c..09529929492821 100755
--- a/src/coreclr/build-runtime.sh
+++ b/src/coreclr/build-runtime.sh
@@ -116,8 +116,6 @@ __CodeCoverage=0
 
 # Set the various build properties here so that CMake and MSBuild can pick them up
 __Compiler=clang
-__CompilerMajorVersion=
-__CompilerMinorVersion=
 __CommonMSBuildArgs=
 __ConfigureOnly=0
 __CrossBuild=0
diff --git a/src/coreclr/tools/aot/ObjWriter/build.sh b/src/coreclr/tools/aot/ObjWriter/build.sh
index 2f7acbd622c987..00aeea948bb269 100644
--- a/src/coreclr/tools/aot/ObjWriter/build.sh
+++ b/src/coreclr/tools/aot/ObjWriter/build.sh
@@ -6,7 +6,8 @@ RepoRoot="$2"
 BuildArch="$3"
 TargetArch="$4"
 BuildType="${5:-Release}"
-CompilerId="$(echo "$6" | tr "[:upper:]" "[:lower:]")"
+Compiler="$(echo "$6" | tr "[:upper:]" "[:lower:]")"
+Compiler="${Compiler:-clang}"
 
 LLVMBranch="release/12.x"
 
@@ -16,24 +17,6 @@ if [ $# -lt 4 ]; then
     exit 1
 fi
 
-if [ -z "$CompilerId" ]; then
-    Compiler=clang
-    CompilerMajorVer=
-    CompilerMinorVer=
-# Expecting a compiler id similar to -clang9 or -gcc10.2. See also eng/native/build-commons.sh.
-elif [[ "$CompilerId" =~ ^-?([a-z]+)(-?([0-9]+)(\.([0-9]+))?)?$ ]]; then
-    Compiler=${BASH_REMATCH[1]}
-    CompilerMajorVer=${BASH_REMATCH[3]}
-    CompilerMinorVer=${BASH_REMATCH[5]}
-    if [[ "$Compiler" == "clang" && -n "$CompilerMajorVer" && "$CompilerMajorVer" -le 6
-        && -z "$CompilerMinorVer" ]]; then
-        CompilerMinorVer=0
-    fi
-else
-    echo "Unexpected compiler identifier '$6'"
-    exit 1
-fi
-
 cd "$ArtifactsDir" || exit 1
 PatchApplied=0
 
@@ -81,7 +64,7 @@ fi
 #   [build flavor] [ninja] [scan-build] [cmakeargs]
 "${RepoRoot}eng/native/gen-buildsys.sh" \
     "$PWD" "$PWD/build/$TargetArch" "$TargetArch" \
-    "$Compiler" "$CompilerMajorVer" "$CompilerMinorVer" "$BuildType" \
+    "$Compiler" "$BuildType" \
     -DCMAKE_BUILD_TYPE="$BuildType" \
     -DCMAKE_INSTALL_PREFIX=install \
     -DLLVM_BUILD_TOOLS=0 \
diff --git a/src/libraries/System.Runtime.InteropServices/tests/TestAssets/NativeExports/NativeExports.csproj b/src/libraries/System.Runtime.InteropServices/tests/TestAssets/NativeExports/NativeExports.csproj
index 5f0b3298ed8f69..cc5a3a284f8c2a 100644
--- a/src/libraries/System.Runtime.InteropServices/tests/TestAssets/NativeExports/NativeExports.csproj
+++ b/src/libraries/System.Runtime.InteropServices/tests/TestAssets/NativeExports/NativeExports.csproj
@@ -27,7 +27,6 @@
     <PropertyGroup>
       <NativeCompiler>$(Compiler)</NativeCompiler>
       <NativeCompiler Condition="'$(NativeCompiler)' == ''">clang</NativeCompiler>
-      <NativeCompiler Condition="$(NativeCompiler.StartsWith('-'))">$(NativeCompiler.TrimStart('-'))</NativeCompiler>
     </PropertyGroup>
 
     <Exec Command="bash -c 'source &quot;$(RepositoryEngineeringDir)/common/native/init-compiler.sh&quot; &quot;$(RepositoryEngineeringDir)/common/native&quot; $(TargetArchitecture) $(NativeCompiler) &amp;&amp; echo $CC'"
diff --git a/src/mono/mono.proj b/src/mono/mono.proj
index c576f971d085f6..79e1be16cfaec6 100644
--- a/src/mono/mono.proj
+++ b/src/mono/mono.proj
@@ -49,10 +49,6 @@
     <MonoCCompiler Condition="'$(MonoCCompiler)' == ''">clang</MonoCCompiler>
     <_CompilerTargetArch Condition="'$(RealTargetArchitecture)' == ''">$(Platform)</_CompilerTargetArch>
     <_CompilerTargetArch Condition="'$(RealTargetArchitecture)' != ''">$(RealTargetArchitecture)</_CompilerTargetArch>
-    <!-- when we use runtime/build.sh -gcc, it is passed to eng/build.sh which sets the raw value to $(Compiler); strip the leading hyphens. -->
-    <MonoCCompiler Condition="$(MonoCCompiler.StartsWith('-'))">$(MonoCCompiler.TrimStart('-'))</MonoCCompiler>
-    <MonoCxxCompiler Condition="'$(MonoCCompiler)' == 'clang'">clang++</MonoCxxCompiler>
-    <MonoCxxCompiler Condition="'$(MonoCCompiler)' == 'gcc'">g++</MonoCxxCompiler>
     <RepositoryEngineeringCommonDir>$([MSBuild]::NormalizeDirectory('$(RepositoryEngineeringDir)', 'common'))</RepositoryEngineeringCommonDir>
     <CrossToolchainFile>$([MSBuild]::NormalizePath('$(RepositoryEngineeringCommonDir)', 'cross', 'toolchain.cmake'))</CrossToolchainFile>
   </PropertyGroup>
diff --git a/src/native/corehost/build.sh b/src/native/corehost/build.sh
index 333f3802f10747..8d2eb46fa914a2 100755
--- a/src/native/corehost/build.sh
+++ b/src/native/corehost/build.sh
@@ -16,8 +16,6 @@ __TargetOS=Linux
 __BuildType=Debug
 __CMakeArgs=""
 __Compiler=clang
-__CompilerMajorVersion=
-__CompilerMinorVersion=
 __CrossBuild=0
 __PortableBuild=1
 __RootBinDir="$__RepoRootDir/artifacts"
diff --git a/src/native/libs/build-native.sh b/src/native/libs/build-native.sh
index 2928934834bd50..1849a2320ae38b 100755
--- a/src/native/libs/build-native.sh
+++ b/src/native/libs/build-native.sh
@@ -31,8 +31,6 @@ __TargetOS=Linux
 __BuildType=Debug
 __CMakeArgs=""
 __Compiler=clang
-__CompilerMajorVersion=
-__CompilerMinorVersion=
 __CrossBuild=0
 __PortableBuild=1
 __RootBinDir="$__RepoRootDir/artifacts"
diff --git a/src/tests/build.sh b/src/tests/build.sh
index 40745ddde67c97..ae26724f9882fe 100755
--- a/src/tests/build.sh
+++ b/src/tests/build.sh
@@ -293,8 +293,6 @@ export __ProjectDir
 __SkipTestWrappers=0
 __BuildTestWrappersOnly=0
 __Compiler=clang
-__CompilerMajorVersion=
-__CompilerMinorVersion=
 __ConfigureOnly=0
 __CopyNativeProjectsAfterCombinedTestBuild=true
 __CopyNativeTestBinaries=0
@@ -394,7 +392,7 @@ if [[ "$__RebuildTests" -ne 0 ]]; then
     echo "Removing test build dir: ${__TestBinDir}"
     rm -rf "${__TestBinDir}"
     echo "Removing test intermediate dir: ${__TestIntermediatesDir}"
-    rm -rf "${__TestIntermediatesDir}" 
+    rm -rf "${__TestIntermediatesDir}"
 fi
 
 build_Tests