configure: Cleanup MacOS and iOS build settings

Makes it easy for users to select which compiler to use.

configure/os/CONFIG.Common.iosCommon

@@ -42,10 +42,6 @@ ARCH_DEP_LDFLAGS += $(ARCH_DEP_FLAGS)
 # Operating system flags
 OP_SYS_CFLAGS += -isysroot $(SDK_DIR) -D__IPHONE_OS_VERSION_MIN_REQUIRED=30200
 
-#--------------------------------------------------
-# Don't try to use precompiled headers when converting sequencer files
-CPPSNCFLAGS += -no-cpp-precomp
-
 #--------------------------------------------------
 # Always compile in debugging symbol table information
 #
@@ -54,13 +50,20 @@ OPT_CXXFLAGS_YES += -g
 
 #-------------------------------------------------------
 # Compiler definitions:
-#   Use clang instead of gcc
-CC = $(GNU_BIN)/clang
-CCC = $(GNU_BIN)/clang++
-GNU_LDLIBS_YES =
+
+CC_GNU  = gcc
+CCC_GNU = g++
+CC_LLVM  = llvm-gcc
+CCC_LLVM = llvm-g++
+CC_CLANG  = clang
+CCC_CLANG = clang++
+
+CC = $(firstword $(wildcard $(GNU_BIN)/$(CC_$(COMPILER))) $(CC_$(COMPILER)))
+CCC = $(firstword $(wildcard $(GNU_BIN)/$(CCC_$(COMPILER))) $(CCC_$(COMPILER)))
 
 #-------------------------------------------------------
 # Linker flags
+GNU_LDLIBS_YES =
 OP_SYS_LDFLAGS += -dynamic -Z -L$(SDK_DIR)/usr/lib -L$(SDK_DIR)/usr/lib/system
 
 #-------------------------------------------------------

configure/os/CONFIG.darwinCommon.darwinCommon

@@ -36,11 +36,6 @@ ARCH_DEP_LDFLAGS += $(ARCH_DEP_FLAGS)
 #
 OP_SYS_CFLAGS += -fno-common
 
-#
-# Don't try to use precompiled headers when converting sequencer files
-#
-CPPSNCFLAGS += -no-cpp-precomp
-
 #
 # Darwin os definition
 #

configure/os/CONFIG_SITE.Common.ios-arm

@@ -19,10 +19,3 @@
 ARCH_CLASS = armv7
 #ARCH_CLASS = armv6 armv7
 #ARCH_CLASS = armv6
-
-
-# Uncomment these two definitions to use g++ instead of clang++
-# which may be needed in some circumstances:
-#
-#CCC = $(GNU_BIN)/c++
-#GNU_LDLIBS_YES = -lgcc

configure/os/CONFIG_SITE.Common.iosCommon

@@ -10,17 +10,29 @@
 
 #IOS_VERSION = 3.2
 #IOS_VERSION = 4.1
+#IOS_VERSION = 4.2
 #IOS_VERSION = 4.3
 IOS_VERSION = 5.0
 
 
-# Most sites will want shared libraries
+# Which compiler to use:
+#   CLANG is preferred for recent versions of Xcode
+#   LLVM uses the llvm-gcc and llvm-g++ compilers
+#   GNU is needed for older versions of Xcode
 
-STATIC_BUILD=NO
-SHARED_LIBRARIES=YES
+COMPILER = CLANG
+#COMPILER = LLVM
+#COMPILER = GNU
 
 
-# Platform path, this is probably correct
+# Most sites will want to build shared libraries (which is the
+# default), but if you get an error from ld while building libCom,
+# try uncommenting this, which is needed for some compiler versions:
+
+#SHARED_LIBRARIES = NO
+
+
+# Get platform path from OS, these are usually correct:
 
 XCODE_PATH := $(shell xcode-select -print-path)
 PLATFORM_DIR = $(XCODE_PATH)/Platforms/$(IOS_PLATFORM).platform