Auto-detect binarybuilder triplet

Make.inc

@@ -232,11 +232,11 @@ INSTALL_F := $(JULIAHOME)/contrib/install.sh 644
 INSTALL_M := $(JULIAHOME)/contrib/install.sh 755
 
 # BinaryBuilder options
-# TODO: Autodiscover triplet
+BINARYBUILDER_TRIPLET = $(shell contrib/normalize_triplet.py $(or $(XC_HOST),$(XC_HOST),$(BUILD_MACHINE)))
 USE_BINARYBUILDER_LLVM := 0
+USE_BINARYBUILDER_OPENBLAS := 0
 # Use the Assertions build
 BINARYBUILDER_LLVM_ASSERTS := 0
-BINARYBUILDER_TRIPLET :=
 
 # LLVM Options
 LLVMROOT := $(build_prefix)

contrib/normalize_triplet.py

@@ -0,0 +1,111 @@
+#!/usr/bin/env python
+
+import re, sys
+
+# This script designed to mimick `src/PlatformNames.jl` in `BinaryProvider.jl`, which has
+# a method `platform_key_abi()` to parse uname-like output into something standarized.
+
+if len(sys.argv) < 2:
+    print("Usage: %s <host triplet>")
+    sys.exit(1)
+
+arch_mapping = {
+    'x86_64': '(x86_|amd)64',
+    'i686': "i\\d86",
+    'aarch64': "aarch64",
+    'arm': "arm(v7l)?",
+    'powerpc64le': "p(ower)?pc64le",
+}
+platform_mapping = {
+    'darwin': "-apple-darwin[\\d\\.]*",
+    'freebsd': "-(.*-)?freebsd[\\d\\.]*",
+    'windows': "-w64-mingw32",
+    'linux': "-(.*-)?linux",
+}
+libc_mapping = {
+    'blank_libc': "",
+    'gnu': "-gnu",
+    'musl': "-musl",
+}
+call_abi_mapping = {
+    'blank_call_abi': "",
+    'eabihf': "eabihf",
+}
+gcc_version_mapping = {
+    'blank_gcc': "",
+    'gcc4': "-gcc4",
+    'gcc7': "-gcc7",
+    'gcc8': "-gcc8",
+}
+cxx_abi_mapping = {
+    'blank_cxx_abi': "",
+    'cxx03': "-cxx03",
+    'cxx11': "-cxx11",
+}
+
+# Helper function to collapse dictionary of mappings down into a regex of
+# named capture groups joined by "|" operators
+c = lambda mapping: "("+"|".join(["(?P<%s>%s)"%(k,v) for (k, v) in mapping.items()]) + ")"
+mondo_regex = re.compile(
+    "^"+
+    c(arch_mapping)+
+    c(platform_mapping)+
+    c(libc_mapping)+
+    c(call_abi_mapping)+
+    c(gcc_version_mapping)+
+    c(cxx_abi_mapping)+
+    "$"
+)
+
+# Apply our mondo regex to our input:
+m = mondo_regex.match(sys.argv[1])
+if m is None:
+    print("ERROR: Unmatchable platform string '%s'!"%(sys.argv[1]))
+    sys.exit(1)
+
+# Helper function to find the single named field within the giant regex
+# that is not `nothing` for each mapping we give it.
+def get_field(m, mapping):
+    g = m.groupdict()
+    for k in mapping:
+        if g[k] is not None:
+            return k
+
+arch = get_field(m, arch_mapping)
+platform = get_field(m, platform_mapping)
+libc = get_field(m, libc_mapping)
+call_abi = get_field(m, call_abi_mapping)
+gcc_version = get_field(m, gcc_version_mapping)
+cxx_abi = get_field(m, cxx_abi_mapping)
+
+def r(x):
+    x = x.replace("blank_call_abi", "")
+    x = x.replace("blank_gcc", "")
+    x = x.replace("blank_cxx_abi", "")
+    x = x.replace("blank_libc", "")
+    return x
+
+def p(x):
+    # These contain characters that can't be easily represented as
+    # capture group names, unfortunately:
+    os_remapping = {
+        'darwin': 'apple-darwin14',
+        'windows': 'w64-mingw32',
+        'freebsd': 'unknown-freebsd11.1',
+    }
+    x = r(x)
+    if x:
+        for k in os_remapping:
+            x = x.replace(k, os_remapping[k])
+        return '-' + x
+    return x
+
+print(arch+p(platform)+p(libc)+r(call_abi)+p(gcc_version)+p(cxx_abi))
+
+# Testing suite:
+# triplets="i686-w64-mingw32 x86_64-pc-linux-musl arm-linux-musleabihf x86_64-linux-gnu arm-linux-gnueabihf x86_64-apple-darwin14 x86_64-unknown-freebsd11.1"
+# for t in $triplets; do
+#     if [[ $(./normalize_triplet.py "$t") != "$t" ]]; then
+#         echo "ERROR: Failed test on $t"
+#     fi
+# done