diff --git a/pkgs/development/compilers/llvm/10/llvm/default.nix b/pkgs/development/compilers/llvm/10/llvm/default.nix
index b40d3070c059..68a4dc3170c8 100644
--- a/pkgs/development/compilers/llvm/10/llvm/default.nix
+++ b/pkgs/development/compilers/llvm/10/llvm/default.nix
@@ -122,6 +122,32 @@ in stdenv.mkDerivation (rec {
     rm test/ExecutionEngine/frem.ll
   '' + ''
     patchShebangs test/BugPoint/compile-custom.ll.py
+  '' + ''
+    # Tweak tests to ignore namespace part of type to support
+    # gcc-12: https://gcc.gnu.org/PR103598.
+    # The change below mangles strings like:
+    #    CHECK-NEXT: Starting llvm::Function pass manager run.
+    # to:
+    #    CHECK-NEXT: Starting {{.*}}Function pass manager run.
+    for f in \
+      test/Other/new-pass-manager.ll \
+      test/Other/new-pm-defaults.ll \
+      test/Other/new-pm-lto-defaults.ll \
+      test/Other/new-pm-thinlto-defaults.ll \
+      test/Other/pass-pipeline-parsing.ll \
+      test/Transforms/Inline/cgscc-incremental-invalidate.ll \
+      test/Transforms/Inline/clear-analyses.ll \
+      test/Transforms/LoopUnroll/unroll-loop-invalidation.ll \
+      test/Transforms/SCCP/ipsccp-preserve-analysis.ll \
+      test/Transforms/SCCP/preserve-analysis.ll \
+      test/Transforms/SROA/dead-inst.ll \
+      test/tools/gold/X86/new-pm.ll \
+      ; do
+      echo "PATCH: $f"
+      substituteInPlace $f \
+        --replace 'Starting llvm::' 'Starting {{.*}}' \
+        --replace 'Finished llvm::' 'Finished {{.*}}'
+    done
   '';
 
   # hacky fix: created binaries need to be run before installation
diff --git a/pkgs/development/compilers/llvm/11/llvm/default.nix b/pkgs/development/compilers/llvm/11/llvm/default.nix
index 8d14ee131bd2..2f1c7eb85e62 100644
--- a/pkgs/development/compilers/llvm/11/llvm/default.nix
+++ b/pkgs/development/compilers/llvm/11/llvm/default.nix
@@ -120,6 +120,32 @@ in stdenv.mkDerivation (rec {
     rm test/ExecutionEngine/frem.ll
   '' + ''
     patchShebangs test/BugPoint/compile-custom.ll.py
+  '' + ''
+    # Tweak tests to ignore namespace part of type to support
+    # gcc-12: https://gcc.gnu.org/PR103598.
+    # The change below mangles strings like:
+    #    CHECK-NEXT: Starting llvm::Function pass manager run.
+    # to:
+    #    CHECK-NEXT: Starting {{.*}}Function pass manager run.
+    for f in \
+      test/Other/new-pass-manager.ll \
+      test/Other/new-pm-defaults.ll \
+      test/Other/new-pm-lto-defaults.ll \
+      test/Other/new-pm-thinlto-defaults.ll \
+      test/Other/pass-pipeline-parsing.ll \
+      test/Transforms/Inline/cgscc-incremental-invalidate.ll \
+      test/Transforms/Inline/clear-analyses.ll \
+      test/Transforms/LoopUnroll/unroll-loop-invalidation.ll \
+      test/Transforms/SCCP/ipsccp-preserve-analysis.ll \
+      test/Transforms/SCCP/preserve-analysis.ll \
+      test/Transforms/SROA/dead-inst.ll \
+      test/tools/gold/X86/new-pm.ll \
+      ; do
+      echo "PATCH: $f"
+      substituteInPlace $f \
+        --replace 'Starting llvm::' 'Starting {{.*}}' \
+        --replace 'Finished llvm::' 'Finished {{.*}}'
+    done
   '';
 
   # hacky fix: created binaries need to be run before installation
diff --git a/pkgs/development/compilers/llvm/12/llvm/default.nix b/pkgs/development/compilers/llvm/12/llvm/default.nix
index bb5676b9d48e..8416a550443f 100644
--- a/pkgs/development/compilers/llvm/12/llvm/default.nix
+++ b/pkgs/development/compilers/llvm/12/llvm/default.nix
@@ -105,6 +105,33 @@ in stdenv.mkDerivation (rec {
     rm test/ExecutionEngine/frem.ll
   '' + ''
     patchShebangs test/BugPoint/compile-custom.ll.py
+  '' + ''
+    # Tweak tests to ignore namespace part of type to support
+    # gcc-12: https://gcc.gnu.org/PR103598.
+    # The change below mangles strings like:
+    #    CHECK-NEXT: Starting llvm::Function pass manager run.
+    # to:
+    #    CHECK-NEXT: Starting {{.*}}Function pass manager run.
+    for f in \
+      test/Other/new-pass-manager.ll \
+      test/Other/new-pm-O0-defaults.ll \
+      test/Other/new-pm-defaults.ll \
+      test/Other/new-pm-lto-defaults.ll \
+      test/Other/new-pm-thinlto-defaults.ll \
+      test/Other/pass-pipeline-parsing.ll \
+      test/Transforms/Inline/cgscc-incremental-invalidate.ll \
+      test/Transforms/Inline/clear-analyses.ll \
+      test/Transforms/LoopUnroll/unroll-loop-invalidation.ll \
+      test/Transforms/SCCP/ipsccp-preserve-analysis.ll \
+      test/Transforms/SCCP/preserve-analysis.ll \
+      test/Transforms/SROA/dead-inst.ll \
+      test/tools/gold/X86/new-pm.ll \
+      ; do
+      echo "PATCH: $f"
+      substituteInPlace $f \
+        --replace 'Starting llvm::' 'Starting {{.*}}' \
+        --replace 'Finished llvm::' 'Finished {{.*}}'
+    done
   '';
 
   # hacky fix: created binaries need to be run before installation
diff --git a/pkgs/development/compilers/llvm/5/llvm/default.nix b/pkgs/development/compilers/llvm/5/llvm/default.nix
index 339c7a36931e..d55f1300ffe5 100644
--- a/pkgs/development/compilers/llvm/5/llvm/default.nix
+++ b/pkgs/development/compilers/llvm/5/llvm/default.nix
@@ -100,6 +100,27 @@ stdenv.mkDerivation ({
     substituteInPlace unittests/Support/CMakeLists.txt \
       --replace "add_subdirectory(DynamicLibrary)" ""
     rm unittests/Support/DynamicLibrary/DynamicLibraryTest.cpp
+  '' + ''
+    # Tweak tests to ignore namespace part of type to support
+    # gcc-12: https://gcc.gnu.org/PR103598.
+    # The change below mangles strings like:
+    #    CHECK-NEXT: Starting llvm::Function pass manager run.
+    # to:
+    #    CHECK-NEXT: Starting {{.*}}Function pass manager run.
+    for f in \
+      test/Other/new-pass-manager.ll \
+      test/Other/new-pm-defaults.ll \
+      test/Other/new-pm-lto-defaults.ll \
+      test/Other/new-pm-thinlto-defaults.ll \
+      test/Other/pass-pipeline-parsing.ll \
+      test/Transforms/Inline/cgscc-incremental-invalidate.ll \
+      test/Transforms/Inline/clear-analyses.ll \
+      ; do
+      echo "PATCH: $f"
+      substituteInPlace $f \
+        --replace 'Starting llvm::' 'Starting {{.*}}' \
+        --replace 'Finished llvm::' 'Finished {{.*}}'
+    done
   '';
 
   # hacky fix: created binaries need to be run before installation
diff --git a/pkgs/development/compilers/llvm/6/llvm/default.nix b/pkgs/development/compilers/llvm/6/llvm/default.nix
index 5847d50a6f9a..746a18612cbf 100644
--- a/pkgs/development/compilers/llvm/6/llvm/default.nix
+++ b/pkgs/development/compilers/llvm/6/llvm/default.nix
@@ -93,6 +93,29 @@ stdenv.mkDerivation ({
     substituteInPlace unittests/Support/CMakeLists.txt \
       --replace "add_subdirectory(DynamicLibrary)" ""
     rm unittests/Support/DynamicLibrary/DynamicLibraryTest.cpp
+  '' + ''
+    # Tweak tests to ignore namespace part of type to support
+    # gcc-12: https://gcc.gnu.org/PR103598.
+    # The change below mangles strings like:
+    #    CHECK-NEXT: Starting llvm::Function pass manager run.
+    # to:
+    #    CHECK-NEXT: Starting {{.*}}Function pass manager run.
+    for f in \
+      test/Other/new-pass-manager.ll \
+      test/Other/new-pm-defaults.ll \
+      test/Other/new-pm-lto-defaults.ll \
+      test/Other/new-pm-thinlto-defaults.ll \
+      test/Other/pass-pipeline-parsing.ll \
+      test/Transforms/Inline/cgscc-incremental-invalidate.ll \
+      test/Transforms/Inline/clear-analyses.ll \
+      test/Transforms/LoopUnroll/unroll-loop-invalidation.ll \
+      test/Transforms/SROA/dead-inst.ll \
+      ; do
+      echo "PATCH: $f"
+      substituteInPlace $f \
+        --replace 'Starting llvm::' 'Starting {{.*}}' \
+        --replace 'Finished llvm::' 'Finished {{.*}}'
+    done
   '';
 
   # hacky fix: created binaries need to be run before installation
diff --git a/pkgs/development/compilers/llvm/7/llvm/default.nix b/pkgs/development/compilers/llvm/7/llvm/default.nix
index cfa4fdf7ac33..57c6d7eb5f38 100644
--- a/pkgs/development/compilers/llvm/7/llvm/default.nix
+++ b/pkgs/development/compilers/llvm/7/llvm/default.nix
@@ -110,6 +110,31 @@ in stdenv.mkDerivation ({
     rm test/ExecutionEngine/frem.ll
   '' + ''
     patchShebangs test/BugPoint/compile-custom.ll.py
+  '' + ''
+    # Tweak tests to ignore namespace part of type to support
+    # gcc-12: https://gcc.gnu.org/PR103598.
+    # The change below mangles strings like:
+    #    CHECK-NEXT: Starting llvm::Function pass manager run.
+    # to:
+    #    CHECK-NEXT: Starting {{.*}}Function pass manager run.
+    for f in \
+      test/Other/new-pass-manager.ll \
+      test/Other/new-pm-defaults.ll \
+      test/Other/new-pm-lto-defaults.ll \
+      test/Other/new-pm-thinlto-defaults.ll \
+      test/Other/pass-pipeline-parsing.ll \
+      test/Transforms/Inline/cgscc-incremental-invalidate.ll \
+      test/Transforms/Inline/clear-analyses.ll \
+      test/Transforms/LoopUnroll/unroll-loop-invalidation.ll \
+      test/Transforms/SCCP/preserve-analysis.ll \
+      test/Transforms/SROA/dead-inst.ll \
+      test/tools/gold/X86/new-pm.ll \
+      ; do
+      echo "PATCH: $f"
+      substituteInPlace $f \
+        --replace 'Starting llvm::' 'Starting {{.*}}' \
+        --replace 'Finished llvm::' 'Finished {{.*}}'
+    done
   '';
 
   # hacky fix: created binaries need to be run before installation
diff --git a/pkgs/development/compilers/llvm/8/llvm/default.nix b/pkgs/development/compilers/llvm/8/llvm/default.nix
index 902a379b7aad..1decdce26a85 100644
--- a/pkgs/development/compilers/llvm/8/llvm/default.nix
+++ b/pkgs/development/compilers/llvm/8/llvm/default.nix
@@ -104,6 +104,32 @@ in stdenv.mkDerivation ({
     rm test/CodeGen/AArch64/wineh4.mir
   '' + ''
     patchShebangs test/BugPoint/compile-custom.ll.py
+  '' + ''
+    # Tweak tests to ignore namespace part of type to support
+    # gcc-12: https://gcc.gnu.org/PR103598.
+    # The change below mangles strings like:
+    #    CHECK-NEXT: Starting llvm::Function pass manager run.
+    # to:
+    #    CHECK-NEXT: Starting {{.*}}Function pass manager run.
+    for f in \
+      test/Other/new-pass-manager.ll \
+      test/Other/new-pm-defaults.ll \
+      test/Other/new-pm-lto-defaults.ll \
+      test/Other/new-pm-thinlto-defaults.ll \
+      test/Other/pass-pipeline-parsing.ll \
+      test/Transforms/Inline/cgscc-incremental-invalidate.ll \
+      test/Transforms/Inline/clear-analyses.ll \
+      test/Transforms/LoopUnroll/unroll-loop-invalidation.ll \
+      test/Transforms/SCCP/ipsccp-preserve-analysis.ll \
+      test/Transforms/SCCP/preserve-analysis.ll \
+      test/Transforms/SROA/dead-inst.ll \
+      test/tools/gold/X86/new-pm.ll \
+      ; do
+      echo "PATCH: $f"
+      substituteInPlace $f \
+        --replace 'Starting llvm::' 'Starting {{.*}}' \
+        --replace 'Finished llvm::' 'Finished {{.*}}'
+    done
   '';
 
   # hacky fix: created binaries need to be run before installation
diff --git a/pkgs/development/compilers/llvm/9/llvm/default.nix b/pkgs/development/compilers/llvm/9/llvm/default.nix
index ed21ac74a1a1..29c0558237c5 100644
--- a/pkgs/development/compilers/llvm/9/llvm/default.nix
+++ b/pkgs/development/compilers/llvm/9/llvm/default.nix
@@ -119,6 +119,32 @@ in stdenv.mkDerivation (rec {
     # Fix x86 gold test on non-x86 platforms
     # (similar fix made to others in this directory previously, FWIW)
     patch -p1 -i  ${./fix-test-on-non-x86-like-others.patch}
+  '' + ''
+    # Tweak tests to ignore namespace part of type to support
+    # gcc-12: https://gcc.gnu.org/PR103598.
+    # The change below mangles strings like:
+    #    CHECK-NEXT: Starting llvm::Function pass manager run.
+    # to:
+    #    CHECK-NEXT: Starting {{.*}}Function pass manager run.
+    for f in \
+      test/Other/new-pass-manager.ll \
+      test/Other/new-pm-defaults.ll \
+      test/Other/new-pm-lto-defaults.ll \
+      test/Other/new-pm-thinlto-defaults.ll \
+      test/Other/pass-pipeline-parsing.ll \
+      test/Transforms/Inline/cgscc-incremental-invalidate.ll \
+      test/Transforms/Inline/clear-analyses.ll \
+      test/Transforms/LoopUnroll/unroll-loop-invalidation.ll \
+      test/Transforms/SCCP/ipsccp-preserve-analysis.ll \
+      test/Transforms/SCCP/preserve-analysis.ll \
+      test/Transforms/SROA/dead-inst.ll \
+      test/tools/gold/X86/new-pm.ll \
+      ; do
+      echo "PATCH: $f"
+      substituteInPlace $f \
+        --replace 'Starting llvm::' 'Starting {{.*}}' \
+        --replace 'Finished llvm::' 'Finished {{.*}}'
+    done
   '';
 
   # hacky fix: created binaries need to be run before installation