toolchain-internal: skip gcc-intermediate when possible

When NPTL support was introduced, gcc required a three stages build
process. Since gcc 4.7, this is no longer necessary, and it is
possible to get back to a two stages build process. This patch takes
advantage of this, by doing a two stages build process when possible.

We introduce a few hidden kconfig options:

 * BR2_GCC_VERSION_NEEDS_THREE_STAGE_BUILD, which is set by the gcc
   Config.in logic to indicate that the compiler might need a three
   stages build. Currently, all versions prior to 4.7.x are selecting
   this kconfig option.

 * BR2_TOOLCHAIN_LIBC_NEEDS_THREE_STAGE_BUILD, which indicates whether
   the C library might need a three stages build. This is the case for
   eglibc, and uClibc when NPTL is enabled.

 * BR2_TOOLCHAIN_NEEDS_THREE_STAGE_BUILD finally is enabled when both
   of the previous options are enabled. It indicates that a three
   stages build is actually needed.

In addition to those options, the uClibc/gcc build logic is changed to
use only a two stages build process when possible.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>

diff --git a/package/eglibc/eglibc.mk b/package/eglibc/eglibc.mk
index fe12299afcf26c374fd21afe41bca656e3486843..0ed908d3984d1edf71058f132068ef84014a738c 100644 (file)
--- a/package/eglibc/eglibc.mk
+++ b/package/eglibc/eglibc.mk
@@ -14,8 +14,9 @@ EGLIBC_LICENSE_FILES = libc/COPYING libc/COPYING.LIB libc/LICENSES
 # cross-compiler and the kernel headers
 EGLIBC_DEPENDENCIES = host-gcc-initial linux-headers host-gawk
 
-# Before eglibc is built, we must have the second stage cross-compiler
-eglibc-build: host-gcc-intermediate
+# Before eglibc is built, we must have the second stage
+# cross-compiler, for some gcc versions
+eglibc-build: $(if $(BR2_TOOLCHAIN_NEEDS_THREE_STAGE_BUILD),host-gcc-intermediate)
 
 EGLIBC_SUBDIR = build
 

diff --git a/package/gcc/Config.in.host b/package/gcc/Config.in.host
index a6acaa25c6ca7fd6f4cd8ca9b992a1c3462d4a9c..7e6df2d9e6b56c3cb827f5c277564c35996ce563 100644 (file)
--- a/package/gcc/Config.in.host
+++ b/package/gcc/Config.in.host
@@ -3,6 +3,12 @@ comment "GCC Options"
 config BR2_GCC_NEEDS_MPC
        bool
 
+# Until gcc 4.7, a three stage build process was needed when using
+# NPTL. This hidden option tells whether gcc is a version that
+# requires this three stage build process.
+config BR2_GCC_VERSION_NEEDS_THREE_STAGE_BUILD
+       bool
+
 choice
        prompt "GCC compiler Version"
        default BR2_GCC_VERSION_4_4_X if BR2_sparc_sparchfleon || BR2_sparc_sparchfleonv8 || BR2_sparc_sparcsfleon || BR2_sparc_sparcsfleonv8
@@ -16,11 +22,13 @@ choice
        config BR2_GCC_VERSION_4_2_2_AVR32_2_1_5
                depends on BR2_avr32
                bool "gcc 4.2.2-avr32-2.1.5"
+               select BR2_GCC_VERSION_NEEDS_THREE_STAGE_BUILD
 
        config BR2_GCC_VERSION_4_3_X
                depends on !BR2_arc && !BR2_avr32 && !BR2_sparc_sparchfleon && !BR2_sparc_sparchfleonv8 && !BR2_sparc_sparcsfleon && !BR2_sparc_sparcsfleonv8 && !BR2_cortex_a5 && !BR2_cortex_a7 && !BR2_cortex_a8 && !BR2_cortex_a9 && !BR2_cortex_a15 && !BR2_x86_atom && !BR2_powerpc_e300c2 && !BR2_powerpc_e300c3 && !BR2_powerpc_e500mc && !BR2_powerpc_464 && !BR2_powerpc_464fp && !BR2_powerpc_476 && !BR2_powerpc_476fp && !BR2_fa526 && !BR2_pj4
                depends on !BR2_ARM_EABIHF
                bool "gcc 4.3.x"
+               select BR2_GCC_VERSION_NEEDS_THREE_STAGE_BUILD
 
        config BR2_GCC_VERSION_4_4_X
                depends on !BR2_arc && !BR2_avr32 && !BR2_cortex_a5 && !BR2_cortex_a7 && !BR2_cortex_a15 && !BR2_x86_atom && !BR2_powerpc_476 && !BR2_powerpc_476fp && !BR2_fa526 && !BR2_pj4
@@ -29,6 +37,7 @@ choice
                depends on !BR2_ARM_EABIHF
                # VFPv4 support appeared in gcc 4.5
                depends on !BR2_ARM_FPU_VFPV4 && !BR2_ARM_FPU_VFPV4D16
+               select BR2_GCC_VERSION_NEEDS_THREE_STAGE_BUILD
 
        config BR2_GCC_VERSION_4_5_X
                depends on !BR2_arc && !BR2_avr32 && !BR2_cortex_a7 && !BR2_cortex_a15 && !BR2_sparc_sparchfleon && !BR2_sparc_sparchfleonv8 && !BR2_sparc_sparcsfleon && !BR2_sparc_sparcsfleonv8 && !BR2_fa526 && !BR2_pj4
@@ -36,11 +45,13 @@ choice
                # ARM EABIhf support appeared in gcc 4.6
                depends on !BR2_ARM_EABIHF
                bool "gcc 4.5.x"
+               select BR2_GCC_VERSION_NEEDS_THREE_STAGE_BUILD
 
        config BR2_GCC_VERSION_4_6_X
                depends on !BR2_arc && !BR2_avr32 && !BR2_bfin && !BR2_cortex_a7 && !BR2_sparc_sparchfleon && !BR2_sparc_sparchfleonv8 && !BR2_sparc_sparcsfleon && !BR2_sparc_sparcsfleonv8 && !BR2_pj4
                select BR2_GCC_NEEDS_MPC
                bool "gcc 4.6.x"
+               select BR2_GCC_VERSION_NEEDS_THREE_STAGE_BUILD
 
        config BR2_GCC_VERSION_4_7_X
                depends on !BR2_arc && !BR2_avr32 && !BR2_bfin && !BR2_sparc_sparchfleon && !BR2_sparc_sparchfleonv8 && !BR2_sparc_sparcsfleon && !BR2_sparc_sparcsfleonv8 && !BR2_pj4

diff --git a/package/gcc/gcc-initial/gcc-initial.mk b/package/gcc/gcc-initial/gcc-initial.mk
index 0eb492fa4dccc90b1b7002a220824bac2a117d90..83767ea5091dc80b5414e7155c1f5f45bc6a1492 100644 (file)
--- a/package/gcc/gcc-initial/gcc-initial.mk
+++ b/package/gcc/gcc-initial/gcc-initial.mk
@@ -29,6 +29,7 @@ HOST_GCC_INITIAL_CONF_OPT = \
        --enable-languages=c \
        --disable-shared \
        --without-headers \
+       --disable-threads \
        --with-newlib \
        --disable-largefile \
        --disable-nls \
@@ -40,4 +41,11 @@ HOST_GCC_INITIAL_CONF_ENV = \
 HOST_GCC_INITIAL_MAKE_OPT = all-gcc
 HOST_GCC_INITIAL_INSTALL_OPT = install-gcc
 
+ifeq ($(BR2_TOOLCHAIN_NEEDS_THREE_STAGE_BUILD),)
+ifeq ($(BR2_GCC_SUPPORTS_FINEGRAINEDMTUNE),y)
+HOST_GCC_INITIAL_MAKE_OPT += all-target-libgcc
+HOST_GCC_INITIAL_INSTALL_OPT += install-target-libgcc
+endif
+endif
+
 $(eval $(host-autotools-package))

diff --git a/package/uclibc/Config.in b/package/uclibc/Config.in
index 92e04e9d6146676e35da577d9b2b96e950f38577..037ca01c0d31308eccadb4c2e6a14798e8c5cec4 100644 (file)
--- a/package/uclibc/Config.in
+++ b/package/uclibc/Config.in
@@ -115,6 +115,7 @@ choice
        config BR2_PTHREADS_NATIVE
                bool "Native POSIX Threading (NPTL)"
                select BR2_TOOLCHAIN_HAS_THREADS
+               select BR2_TOOLCHAIN_LIBC_NEEDS_THREE_STAGE_BUILD
                depends on !BR2_arc
                depends on !BR2_avr32
                depends on !BR2_bfin

diff --git a/package/uclibc/uclibc.mk b/package/uclibc/uclibc.mk
index 39877bbbf99582d62946cefa5a267b2cc821068d..181a772fb3536cde15e9d4ad494061d03ba2b4a9 100644 (file)
--- a/package/uclibc/uclibc.mk
+++ b/package/uclibc/uclibc.mk
@@ -22,8 +22,9 @@ UCLIBC_INSTALL_STAGING = YES
 # cross-compiler and the kernel headers
 UCLIBC_DEPENDENCIES = host-gcc-initial linux-headers
 
-# Before uClibc is built, we must have the second stage cross-compiler
-uclibc-build: host-gcc-intermediate
+# Before uClibc is built, we must have the second stage
+# cross-compiler, for some gcc versions, and when NPTL is used.
+uclibc-build: $(if $(BR2_TOOLCHAIN_NEEDS_THREE_STAGE_BUILD),host-gcc-intermediate)
 
 # specifying UCLIBC_CONFIG_FILE on the command-line overrides the .config
 # setting.

diff --git a/toolchain/Config.in b/toolchain/Config.in
index 9d1e68f8fce9bce9e0ca3c3bcfbbf8cc7e55c908..27f7b50bc1168c9a318699f575794cbfa7d9731f 100644 (file)
--- a/toolchain/Config.in
+++ b/toolchain/Config.in
@@ -1,5 +1,13 @@
 menu "Toolchain"
 
+config BR2_TOOLCHAIN_NEEDS_THREE_STAGE_BUILD
+       bool
+       default y if BR2_TOOLCHAIN_LIBC_NEEDS_THREE_STAGE_BUILD && \
+               BR2_GCC_VERSION_NEEDS_THREE_STAGE_BUILD
+
+config BR2_TOOLCHAIN_LIBC_NEEDS_THREE_STAGE_BUILD
+       bool
+
 # Should be selected for glibc or eglibc
 config BR2_TOOLCHAIN_USES_GLIBC
        bool
@@ -10,6 +18,7 @@ config BR2_TOOLCHAIN_USES_GLIBC
        select BR2_TOOLCHAIN_HAS_THREADS
        select BR2_TOOLCHAIN_HAS_THREADS_DEBUG
        select BR2_TOOLCHAIN_HAS_SHADOW_PASSWORDS
+       select BR2_TOOLCHAIN_LIBC_NEEDS_THREE_STAGE_BUILD
 
 config BR2_TOOLCHAIN_USES_UCLIBC
        bool