Add GCC-11 to workflow (#417)

Remove -pedantic-errors flag for gcc-11.
Update table in README regarding supported compiler versions

Co-authored-by: Laurence Kedward <[email protected]>

Author: awvwgk

.github/workflows/CI.yml

@@ -21,7 +21,7 @@ jobs:
       fail-fast: false
       matrix:
         os: [ubuntu-latest, macos-latest]
-        gcc_v: [7, 8, 9, 10] # Version of GFortran we want to use.
+        gcc_v: [7, 8, 9, 10, 11] # Version of GFortran we want to use.
     env:
       FC: gfortran-${{ matrix.gcc_v }}
       GCC_V: ${{ matrix.gcc_v }}

CMakeLists.txt

@@ -24,7 +24,9 @@ if(CMAKE_Fortran_COMPILER_ID STREQUAL GNU)
   add_compile_options(-Wconversion-extra)
   # -pedantic-errors triggers a false positive for optional arguments of elemental functions,
   # see test_optval and https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95446
-  add_compile_options(-pedantic-errors)
+  if(CMAKE_Fortran_COMPILER_VERSION VERSION_LESS 11.0)
+    add_compile_options(-pedantic-errors)
+  endif()
   if(CMAKE_Fortran_COMPILER_VERSION VERSION_GREATER_EQUAL 8.0)
     add_compile_options(-std=f2018)
   else()

README.md

@@ -87,8 +87,8 @@ The following combinations are tested on the default branch of stdlib:
 
 Name | Version | Platform | Architecture
 --- | --- | --- | ---
-GCC Fortran | 7, 8, 9, 10 | Ubuntu 20.04 | x86_64
-GCC Fortran | 7, 8, 9, 10 | MacOS Catalina 10.15 | x86_64
+GCC Fortran | 7, 8, 9, 10, 11 | Ubuntu 20.04 | x86_64
+GCC Fortran | 7, 8, 9, 10, 11 | MacOS Catalina 10.15 | x86_64
 GCC Fortran | 8 | Windows Server 2019 | x86_64
 GCC Fortran (MSYS) | 10 | Windows Server 2019 | x86_64
 GCC Fortran (MinGW) | 10 | Windows Server 2019 | x86_64, i686