Enable building compiler-rt for a specific LLVM triple with GCC.

Author: vadimcn

make/platform/triple.mk

@@ -0,0 +1,27 @@
+# This "platform" file is intended for building compiler-rt using gcc.
+# The actual target platform is selected by setting the TargetTriple variable to the corresponding LLVM triple.
+
+Description := Static runtime libraries for platforms selected by 'TargetTriple'
+
+# Provide defaults for the required vars
+ifndef CC
+	CC := gcc
+endif
+ifndef CFLAGS
+	CFLAGS := -Wall -O3
+endif
+
+Configs := runtime
+
+Arch := $(word 1,$(subst -, ,$(TargetTriple)))
+ifeq ($(Arch),i686)
+	Arch := i386
+else ifeq ($(Arch),arm)
+	Arch := armv7
+endif
+
+# Filter out stuff that gcc cannot compile (these are only needed for clang-generated code anywasys).
+CommonFunctions_gcc := $(filter-out atomic enable_execute_stack,$(CommonFunctions))
+
+FUNCTIONS.runtime := $(CommonFunctions_gcc) $(value ArchFunctions.$(Arch))
+