[openwrt/openwrt] toolchain: gcc: make config consistent with glibc/musl

[LEDE Commits]

ansuel pushed a commit to openwrt/openwrt.git, branch main:
https://git.openwrt.org/57841c83d9c1503a19212766639d17ae5019bb8c

commit 57841c83d9c1503a19212766639d17ae5019bb8c
Author: Konstantin Demin <rockdrilla at gmail.com>
AuthorDate: Fri May 2 13:42:42 2025 +0300

    toolchain: gcc: make config consistent with glibc/musl
    
    I've observed configuration drift for GCC between musl and glibc
    (especially it's final stage):
    
      # musl
      lt_cv_prog_compiler_static_works=yes
      lt_cv_prog_compiler_static_works_CXX=yes
      lt_cv_sys_max_cmd_len=1572864
    
      # glibc
      lt_cv_prog_compiler_static_works=no
      lt_cv_prog_compiler_static_works_CXX=no
      lt_cv_sys_max_cmd_len=512
    
    These changes should prevent this issue in future:
    
      export lt_cv_prog_compiler_static_works=yes
      export lt_cv_prog_compiler_static_works_CXX=yes
      export lt_cv_sys_max_cmd_len=1572864
    
    Also:
    
    - provide custom autotools/libtool variables via properly named
      variable ("GCC_CONFIGURE_VARS"),
    - move variables from "GCC_MAKE" to "GCC_CONFIGURE_VARS"
      (at this moment only "gcc_cv_libc_provides_ssp=yes" for musl),
    - propagate it's usage for both "./configure" and "make".
    
    Signed-off-by: Konstantin Demin <rockdrilla at gmail.com>
    Link: https://github.com/openwrt/openwrt/pull/18646
    Signed-off-by: Christian Marangi <ansuelsmth at gmail.com>
---
 toolchain/gcc/common.mk        |  8 ++++++++
 toolchain/gcc/final/Makefile   | 14 +++++++++++---
 toolchain/gcc/initial/Makefile |  2 ++
 toolchain/gcc/minimal/Makefile | 10 ++++++++--
 4 files changed, 29 insertions(+), 5 deletions(-)

diff --git a/toolchain/gcc/common.mk b/toolchain/gcc/common.mk
index 0ccf55bd31..a5837493c2 100644
--- a/toolchain/gcc/common.mk
+++ b/toolchain/gcc/common.mk
@@ -89,6 +89,13 @@ else
   GRAPHITE_CONFIGURE:= --without-isl --without-cloog
 endif
 
+## sane and common defaults for different libc implementations
+export lt_cv_prog_compiler_static_works=yes
+export lt_cv_prog_compiler_static_works_CXX=yes
+export lt_cv_sys_max_cmd_len=1572864
+
+GCC_CONFIGURE_VARS :=
+
 GCC_CONFIGURE:= \
 	SHELL="$(BASH)" \
 	$(HOST_SOURCE_DIR)/configure \
@@ -222,6 +229,7 @@ endif
 
 define Host/Configure
 	(cd $(GCC_BUILD_DIR) && rm -f config.cache; \
+		$(if $(strip $(GCC_CONFIGURE_VARS)),export $(GCC_CONFIGURE_VARS)); \
 		$(GCC_CONFIGURE) \
 	);
 endef
diff --git a/toolchain/gcc/final/Makefile b/toolchain/gcc/final/Makefile
index 78a5576bff..6a190a14d7 100644
--- a/toolchain/gcc/final/Makefile
+++ b/toolchain/gcc/final/Makefile
@@ -17,7 +17,7 @@ ifndef CONFIG_USE_GLIBC
 endif
 
 ifdef CONFIG_USE_MUSL
-  GCC_MAKE += gcc_cv_libc_provides_ssp=yes
+  GCC_CONFIGURE_VARS += gcc_cv_libc_provides_ssp=yes
 endif
 
 ifneq ($(CONFIG_SJLJ_EXCEPTIONS),)
@@ -39,6 +39,7 @@ define Host/Configure
 	$(CleanupToolchain)
 	mkdir -p $(GCC_BUILD_DIR)
 	(cd $(GCC_BUILD_DIR) && rm -f config.cache; \
+		$(if $(strip $(GCC_CONFIGURE_VARS)),export $(GCC_CONFIGURE_VARS)); \
 		$(GCC_CONFIGURE) \
 	);
 endef
@@ -53,7 +54,10 @@ endif
 
 define Host/Compile
 	$(FixGogccCrt)
-	+$(GCC_MAKE) $(HOST_JOBS) -C $(GCC_BUILD_DIR) all
+
+	$(GCC_MAKE) $(HOST_JOBS) -C $(GCC_BUILD_DIR) \
+		$(GCC_CONFIGURE_VARS) \
+		all
 endef
 
 define SetupExtraArch
@@ -71,7 +75,11 @@ endef
 
 define Host/Install
 	$(CleanupToolchain)
-	+$(GCC_MAKE) $(HOST_JOBS) -C $(GCC_BUILD_DIR) install
+
+	+$(GCC_MAKE) $(HOST_JOBS) -C $(GCC_BUILD_DIR) \
+		$(GCC_CONFIGURE_VARS) \
+		install
+
 	# Set up the symlinks to enable lying about target name.
 	set -e; \
 	(cd $(TOOLCHAIN_DIR); \
diff --git a/toolchain/gcc/initial/Makefile b/toolchain/gcc/initial/Makefile
index 7cb4a73dbc..6b8a66798b 100644
--- a/toolchain/gcc/initial/Makefile
+++ b/toolchain/gcc/initial/Makefile
@@ -12,6 +12,7 @@ GCC_CONFIGURE += \
 
 define Host/Compile
 	+$(GCC_MAKE) $(HOST_JOBS) -C $(GCC_BUILD_DIR) \
+		$(GCC_CONFIGURE_VARS) \
 		all-build-libiberty \
 		all-gcc \
 		all-target-libgcc
@@ -19,6 +20,7 @@ endef
 
 define Host/Install
 	+$(GCC_MAKE) $(HOST_JOBS) -C $(GCC_BUILD_DIR) \
+		$(GCC_CONFIGURE_VARS) \
 		install-gcc \
 		install-target-libgcc
 
diff --git a/toolchain/gcc/minimal/Makefile b/toolchain/gcc/minimal/Makefile
index 31d6f675ab..83c17c8823 100644
--- a/toolchain/gcc/minimal/Makefile
+++ b/toolchain/gcc/minimal/Makefile
@@ -13,11 +13,17 @@ GCC_CONFIGURE += \
 	--disable-threads
 
 define Host/Compile
-	+$(GCC_MAKE) $(HOST_JOBS) -C $(GCC_BUILD_DIR) all-gcc all-target-libgcc
+	+$(GCC_MAKE) $(HOST_JOBS) -C $(GCC_BUILD_DIR) \
+		$(GCC_CONFIGURE_VARS) \
+		all-gcc \
+		all-target-libgcc
 endef
 
 define Host/Install
-	$(GCC_MAKE) -C $(GCC_BUILD_DIR) install-gcc install-target-libgcc
+	$(GCC_MAKE) -C $(GCC_BUILD_DIR) \
+		$(GCC_CONFIGURE_VARS) \
+		install-gcc \
+		install-target-libgcc
 endef
 
 define Host/Clean