Reduce size of AOT SDK images by removing unnecessary packages

eng/dockerfile-templates/sdk/Dockerfile.linux.aot

@@ -7,28 +7,80 @@
     set isUbuntu to find(OS_ARCH_HYPHENATED, "Ubuntu") >= 0 ^
     set ubuntuVersion to when(find(OS_VERSION, "jammy") >= 0, "jammy", "noble") ^
 
+    _ Native AOT only requires gcc. Native AOT in .NET really only needs a linker and something to drive the linker.
+      The runtime falls back to using gcc to drive linking when clang is not present, and both use the same bfd linker
+      under the hood, so dropping clang/llvm meaningfully shrinks the image. This optimization was made in .NET 11,
+      hence the conditional below. ^
+    set useGcc to dotnetVersion != "8.0" && dotnetVersion != "9.0" && dotnetVersion != "10.0" ^
+
+    _ The gcc package alone isn't always sufficient to link Native AOT binaries:
+      - Alpine: gcc pulls in binutils, but musl-dev (crt objects/headers) must be added.
+      - Azure Linux 3.0: gcc pulls in neither binutils (objcopy/ld) nor glibc-devel
+        (crt objects and -ldl/-lrt), so both are added explicitly.
+      - Azure Linux 4.0 and Ubuntu: gcc transitively pulls in binutils and libc dev
+        packages, so gcc alone is enough.
+      Installing these specific packages avoids the much larger build-base /
+      build-essential meta-packages that bundle make, g++, autotools, etc. ^
+
     set pkgs to cat(sort(
-        when(isAlpine,
-        [
-            "build-base",
-            "clang",
-            "zlib-dev"
-        ],
-        when(isAzureLinux,
-        when(OS_VERSION_NUMBER = "3.0",
-        [
-            "build-essential",
-            "clang",
-            "zlib-devel"
-        ],
-        [
-            "gcc"
-        ]),
-        [
-            "clang",
-            "zlib1g-dev",
-            "llvm"
-        ]))))
+        when(
+            useGcc,
+            when(
+                isAlpine,
+                [
+                    "gcc",
+                    "musl-dev",
+                    "zlib-dev"
+                ],
+                when(
+                    isAzureLinux,
+                    when(
+                        OS_VERSION_NUMBER = "3.0",
+                        [
+                            "binutils",
+                            "gcc",
+                            "glibc-devel",
+                            "zlib-devel"
+                        ],
+                        [
+                            "gcc"
+                        ]
+                    ),
+                    [
+                        "gcc",
+                        "zlib1g-dev"
+                    ]
+                )
+            ),
+            when(
+                isAlpine,
+                [
+                    "build-base",
+                    "clang",
+                    "zlib-dev"
+                ],
+                when(
+                    isAzureLinux,
+                    when(
+                        OS_VERSION_NUMBER = "3.0",
+                        [
+                            "build-essential",
+                            "clang",
+                            "zlib-devel"
+                        ],
+                        [
+                            "gcc"
+                        ]
+                    ),
+                    [
+                        "clang",
+                        "zlib1g-dev",
+                        "llvm"
+                    ]
+                )
+            )
+        )
+    ))
 
 }}ARG REPO=mcr.microsoft.com/dotnet/sdk
 FROM {{baseImageTag}}

src/sdk/11.0/alpine3.23-aot/amd64/Dockerfile

@@ -2,6 +2,6 @@ ARG REPO=mcr.microsoft.com/dotnet/sdk
 FROM $REPO:11.0.100-preview.5-alpine3.23-amd64
 
 RUN apk add --upgrade --no-cache \
-        build-base \
-        clang \
+        gcc \
+        musl-dev \
         zlib-dev

src/sdk/11.0/alpine3.23-aot/arm64v8/Dockerfile

@@ -2,6 +2,6 @@ ARG REPO=mcr.microsoft.com/dotnet/sdk
 FROM $REPO:11.0.100-preview.5-alpine3.23-arm64v8
 
 RUN apk add --upgrade --no-cache \
-        build-base \
-        clang \
+        gcc \
+        musl-dev \
         zlib-dev

src/sdk/11.0/azurelinux3.0-aot/amd64/Dockerfile

@@ -2,7 +2,8 @@ ARG REPO=mcr.microsoft.com/dotnet/sdk
 FROM $REPO:11.0.100-preview.5-azurelinux3.0-amd64
 
 RUN tdnf install -y \
-        build-essential \
-        clang \
+        binutils \
+        gcc \
+        glibc-devel \
         zlib-devel \
     && tdnf clean all

src/sdk/11.0/azurelinux3.0-aot/arm64v8/Dockerfile

@@ -2,7 +2,8 @@ ARG REPO=mcr.microsoft.com/dotnet/sdk
 FROM $REPO:11.0.100-preview.5-azurelinux3.0-arm64v8
 
 RUN tdnf install -y \
-        build-essential \
-        clang \
+        binutils \
+        gcc \
+        glibc-devel \
         zlib-devel \
     && tdnf clean all

src/sdk/11.0/resolute-aot/amd64/Dockerfile

@@ -3,7 +3,6 @@ FROM $REPO:11.0.100-preview.5-resolute-amd64
 
 RUN apt-get update \
     && apt-get install -y --no-install-recommends \
-        clang \
-        llvm \
+        gcc \
         zlib1g-dev \
     && rm -rf /var/lib/apt/lists/*

src/sdk/11.0/resolute-aot/arm64v8/Dockerfile

@@ -3,7 +3,6 @@ FROM $REPO:11.0.100-preview.5-resolute-arm64v8
 
 RUN apt-get update \
     && apt-get install -y --no-install-recommends \
-        clang \
-        llvm \
+        gcc \
         zlib1g-dev \
     && rm -rf /var/lib/apt/lists/*