From 241bdc4bd78e8daf73244278e076d8588394a3af Mon Sep 17 00:00:00 2001
From: Elliot Saba <staticfloat@gmail.com>
Date: Mon, 12 Nov 2018 16:10:44 +0800
Subject: [PATCH] Add `:gcc5` and `:gcc6` as valid GCC choices for
 future-proofing (#139)

`platform_matches()` will consider `:gcc4`, `:gcc5` and `:gcc6` as all
matching at this point, as we only really care about libgfortran version.
The latest compatible release should be the one that gets downloaded
in the event of an ambiguity.
---
 src/PlatformNames.jl | 20 +++++++++++++++++---
 test/runtests.jl     | 32 +++++++++++++++++++++++++++++++-
 2 files changed, 48 insertions(+), 4 deletions(-)

diff --git a/src/PlatformNames.jl b/src/PlatformNames.jl
index 36f7474..a36ef69 100644
--- a/src/PlatformNames.jl
+++ b/src/PlatformNames.jl
@@ -10,7 +10,7 @@ end
 # We need to track our compiler ABI compatibility.
 struct CompilerABI
     # Major GCC version that we're locked into.
-    # Can be [:gcc4, :gcc7, :gcc8, :gcc_any]
+    # Can be [:gcc4, :gcc5, :gcc6, :gcc7, :gcc8, :gcc_any]
     gcc_version::Symbol
 
     # Whether we're using cxx11abi strings
@@ -18,7 +18,7 @@ struct CompilerABI
     cxx_abi::Symbol
 
     function CompilerABI(gcc_version::Symbol = :gcc_any, cxx_abi::Symbol = :cxx_any)
-        if !in(gcc_version, [:gcc4, :gcc7, :gcc8, :gcc_any])
+        if !in(gcc_version, [:gcc4, :gcc5, :gcc6, :gcc7, :gcc8, :gcc_any])
             throw(ArgumentError("Unsupported GCC major version '$gcc_version'"))
         end
 
@@ -389,6 +389,8 @@ function platform_key_abi(machine::AbstractString)
     gcc_version_mapping = Dict(
         :gcc_any => "",
         :gcc4 => "-gcc4",
+        :gcc5 => "-gcc5",
+        :gcc6 => "-gcc6",
         :gcc7 => "-gcc7",
         :gcc8 => "-gcc8",
     )
@@ -703,9 +705,21 @@ function platforms_match(a::Platform, b::Platform)
     function flexible_constraints(a, b)
         ac = compiler_abi(a)
         bc = compiler_abi(b)
+
+        # Map from GCC version to libgfortran SO version
+        gfmap = Dict(
+            :gcc4 => 3,
+            :gcc5 => 3,
+            :gcc6 => 3,
+            :gcc7 => 4,
+            :gcc8 => 5,
+        )
+
+        # We consider two GCC versions to match if their libgfortran
+        # versions match; e.g. :gcc4 and :gcc5 match.
         gcc_match = (ac.gcc_version == :gcc_any
                   || bc.gcc_version == :gcc_any
-                  || ac.gcc_version == bc.gcc_version)
+                  || gfmap[ac.gcc_version] == gfmap[bc.gcc_version])
         cxx_match = (ac.cxx_abi == :cxx_any
                   || bc.cxx_abi == :cxx_any
                   || ac.cxx_abi == bc.cxx_abi)
diff --git a/test/runtests.jl b/test/runtests.jl
index ddf358a..9c616eb 100644
--- a/test/runtests.jl
+++ b/test/runtests.jl
@@ -271,6 +271,20 @@ end
         @test !BinaryProvider.platforms_match(Linux(:x86_64), UnknownPlatform())
         @test !BinaryProvider.platforms_match(Linux(:x86_64, compiler_abi=CompilerABI(:gcc7)), Linux(:x86_64, compiler_abi=CompilerABI(:gcc8)))
         @test !BinaryProvider.platforms_match(Linux(:x86_64, compiler_abi=CompilerABI(:gcc7, :cxx11)), Linux(:x86_64, compiler_abi=CompilerABI(:gcc7, :cxx03)))
+
+        # Test that :gcc4 matches with :gcc5 and :gcc6, as we only care aobut libgfortran version
+        @test BinaryProvider.platforms_match(
+            Linux(:x86_64; compiler_abi=CompilerABI(:gcc4)),
+            Linux(:x86_64; compiler_abi=CompilerABI(:gcc5)),
+        )
+        @test BinaryProvider.platforms_match(
+            Linux(:x86_64; compiler_abi=CompilerABI(:gcc4)),
+            Linux(:x86_64; compiler_abi=CompilerABI(:gcc6)),
+        )
+        @test BinaryProvider.platforms_match(
+            Linux(:x86_64; compiler_abi=CompilerABI(:gcc5)),
+            Linux(:x86_64; compiler_abi=CompilerABI(:gcc6)),
+        )
     end
 
     @testset "DL name/version parsing" begin
@@ -789,21 +803,37 @@ end
 
 @testset "choose_download" begin
     platforms = Dict(
+        # Typical binning test
         Linux(:x86_64, compiler_abi=CompilerABI(:gcc4)) => "linux4",
         Linux(:x86_64, compiler_abi=CompilerABI(:gcc7)) => "linux7",
         Linux(:x86_64, compiler_abi=CompilerABI(:gcc8)) => "linux8",
+
+        # Ambiguity test
+        Linux(:aarch64, compiler_abi=CompilerABI(:gcc4)) => "linux4",
+        Linux(:aarch64, compiler_abi=CompilerABI(:gcc5)) => "linux5",
+
         MacOS(:x86_64, compiler_abi=CompilerABI(:gcc4)) => "mac4",
         Windows(:x86_64, compiler_abi=CompilerABI(:gcc_any, :cxx11)) => "win",
     )
 
     @test choose_download(platforms, Linux(:x86_64)) == "linux8"
     @test choose_download(platforms, Linux(:x86_64, compiler_abi=CompilerABI(:gcc7))) == "linux7"
-
+    
+    # Ambiguity test
+    @test choose_download(platforms, Linux(:aarch64)) == "linux5"
+    @test choose_download(platforms, Linux(:aarch64; compiler_abi=CompilerABI(:gcc4))) == "linux5"
+    @test choose_download(platforms, Linux(:aarch64; compiler_abi=CompilerABI(:gcc5))) == "linux5"
+    @test choose_download(platforms, Linux(:aarch64; compiler_abi=CompilerABI(:gcc6))) == "linux5"
+    @test choose_download(platforms, Linux(:aarch64; compiler_abi=CompilerABI(:gcc7))) == nothing
+    
     @test choose_download(platforms, MacOS(:x86_64)) == "mac4"
     @test choose_download(platforms, MacOS(:x86_64, compiler_abi=CompilerABI(:gcc7))) == nothing
 
     @test choose_download(platforms, Windows(:x86_64, compiler_abi=CompilerABI(:gcc_any, :cxx11))) == "win"
     @test choose_download(platforms, Windows(:x86_64, compiler_abi=CompilerABI(:gcc_any, :cxx03))) == nothing
+   
+    # Poor little guy
+    @test choose_download(platforms, FreeBSD(:x86_64)) == nothing
 end
 
 # Use `build_libfoo_tarball.jl` in the BinaryBuilder.jl repository to generate more of these