From 2c6ef60a81910597635913e4c3a19f3e235fe58b Mon Sep 17 00:00:00 2001
From: Waqar Ahmed Khan <waahm7@gmail.com>
Date: Thu, 19 Dec 2024 08:48:03 -0800
Subject: [PATCH] Fix CI for GCC-13 on Ubuntu-18 (#700)

---
 .github/workflows/ci.yml | 53 ++++++++++++++++++++++++++--------------
 1 file changed, 35 insertions(+), 18 deletions(-)

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index b89f046ef..47c37e5a6 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -61,31 +61,48 @@ jobs:
     strategy:
       matrix:
         compiler:
-          - clang-3
-          - clang-6
-          - clang-8
-          - clang-9
-          - clang-10
-          - clang-11
-          - clang-15
-          - clang-17
-          - gcc-4.8
-          - gcc-5
-          - gcc-6
-          - gcc-7
-          - gcc-8
-          - gcc-11
-          # - gcc-13 TODO: figure out why its not passing
+          - name: clang-3
+          - name: clang-6
+          - name: clang-8
+          - name: clang-9
+          - name: clang-10
+          - name: clang-11
+          - name: clang-15
+          - name: clang-17
+          - name: gcc-4.8
+          - name: gcc-5
+          - name: gcc-6
+          - name: gcc-7
+          - name: gcc-8
+          - name: gcc-11
+          - name: gcc-13
+          # See Issue: https://github.com/llvm/llvm-project/issues/59007. Although this issue 
+          # has been fixed in LLVM, the fix will probably not propagate to older versions of Ubuntu and GCC 13.1. 
+          #
+          # Starting with GLIBC version 2.34, the `dn_expand` function, previously found in `libresolv.so`, was moved to `libc.so`. This 
+          # function is used internally by the `getaddrinfo()` system call.
+          #
+          # In our setup (As of December 2024), we are using an Ubuntu 18 Docker image on a newer Ubuntu host. 
+          # However, due to compatibility issues between newer libasan.so in GCC 13.1
+          # and the older Ubuntu image, the linker does not link with `libresolv.so`. 
+          # This results in crashes in `getaddrinfo()` since Ubuntu-18 GLIBC is 2.31.
+          #
+          # This problem does not occur on Ubuntu 22 and newer because GLIBC versions 2.34 
+          # and above include `dn_expand` in `libc.so`, eliminating the dependency on 
+          # `libresolv.so`.
+          #
+          # We can bypass this problem by linking with "resolv" manually until we bump 
+          # our base Linux image to Ubuntu 22.
+            extra-build-flag: --cmake-extra=-DCMAKE_EXE_LINKER_FLAGS="-lresolv" 
     steps:
     - uses: aws-actions/configure-aws-credentials@v4
       with:
         role-to-assume: ${{ env.CRT_CI_ROLE }}
         aws-region: ${{ env.AWS_DEFAULT_REGION }}
-    # We can't use the `uses: docker://image` version yet, GitHub lacks authentication for actions -> packages
-    - name: Build ${{ env.PACKAGE_NAME }}
+    - name: Build ${{ matrix.compiler.name }}
       run: |
         aws s3 cp s3://aws-crt-test-stuff/ci/${{ env.BUILDER_VERSION }}/linux-container-ci.sh ./linux-container-ci.sh && chmod a+x ./linux-container-ci.sh
-        ./linux-container-ci.sh ${{ env.BUILDER_VERSION }} aws-crt-${{ env.LINUX_BASE_IMAGE }} build -p ${{ env.PACKAGE_NAME }} --compiler=${{ matrix.compiler }}
+        ./linux-container-ci.sh ${{ env.BUILDER_VERSION }} aws-crt-${{ env.LINUX_BASE_IMAGE }} build -p ${{ env.PACKAGE_NAME }} --compiler=${{ matrix.compiler.name }} ${{ matrix.compiler.extra-build-flag }}
 
   linux-debug:
     runs-on: ubuntu-24.04 # latest