gcc: enable libasan and libubsan

This allows to use GCC address and undefined behavior sanitizers.

ASLR must be disabled for the address sanitizer to work (otherwise there
is an mmap failure during initialization).

The implementation is based on the existing ones for other POSIX-ish
operating systems (mainly Linux, FreeBSD, NetBSD, as seemed
appropriate). The main difficulty is that the sanitizer intercepts
various C library calls but also needs the original functions. This is
implemented either by direct syscalls (when simple enough), or with
dlopen to locate the original symbol in libroot.

Only lightly tested, but it already allowed me to find a bug in one of
my projects.

sys-devel/gcc/gcc-13.3.0_2023_08_10.recipe

@@ -5,7 +5,7 @@ HOMEPAGE="https://gcc.gnu.org/"
 COPYRIGHT="1988-2023 Free Software Foundation, Inc."
 LICENSE="GNU GPL v3
 	GNU LGPL v3"
-REVISION="3"
+REVISION="4"
 gccVersion="${portVersion%%_*}"
 SOURCE_URI="https://ftpmirror.gnu.org/gcc/gcc-$gccVersion/gcc-$gccVersion.tar.xz
 	https://ftp.gnu.org/gnu/gcc/gcc-$gccVersion/gcc-$gccVersion.tar.xz"
@@ -17,6 +17,9 @@ PATCHES="gcc-$portVersion.patchset
 ARCHITECTURES="all !x86_gcc2"
 SECONDARY_ARCHITECTURES="x86"
 
+libasanSoVersion="8"
+libasanLibVersion="8.0.0"
+
 libatomicSoVersion="1"
 libatomicLibVersion="1.2.0"
 
@@ -41,6 +44,9 @@ libsspLibVersion="0.0.0"
 libstdcxxSoVersion="6"
 libstdcxxLibVersion="6.0.32"
 
+libubsanSoVersion="1"
+libubsanLibVersion="1.0.0"
+
 PROVIDES="
 	gcc$secondaryArchSuffix = $portVersion compat >= 7
 	cmd:c++$secondaryArchSuffix = $portVersion compat >= 7
@@ -115,6 +121,7 @@ distribution. This package contains the shared libraries for the runtime \
 loader, so it is required for executing most c/c++ programs."
 PROVIDES_syslibs="
 	gcc${secondaryArchSuffix}_syslibs = $portVersion compat >= 7
+	lib:libasan$secondaryArchSuffix = $libasanLibVersion compat >= $libasanSoVersion
 	lib:libatomic$secondaryArchSuffix = $libatomicLibVersion compat >= $libatomicSoVersion
 	lib:libgcc_s$secondaryArchSuffix = $libgccLibVersion compat >= $libgccSoVersion
 	lib:libgfortran$secondaryArchSuffix = $libgfortranLibVersion compat >= $libgfortranSoVersion
@@ -123,6 +130,7 @@ PROVIDES_syslibs="
 	lib:libssp$secondaryArchSuffix = $libsspLibVersion compat >= $libsspSoVersion
 	lib:libstdc++$secondaryArchSuffix = $libstdcxxLibVersion compat >= $libstdcxxSoVersion
 	lib:libsupc++$secondaryArchSuffix = $portVersion compat >= 7
+	lib:libubsan$secondaryArchSuffix = $libubsanLibVersion compat >= $libubsanSoVersion
 	"
 REQUIRES_syslibs="
 	haiku$secondaryArchSuffix
@@ -135,6 +143,7 @@ contains the set of gcc's C/C++-runtime libraries and headers that is \
 required by Haiku's build system when building Haiku."
 PROVIDES_syslibs_devel="
 	gcc${secondaryArchSuffix}_syslibs_devel = $portVersion compat >= 7
+	devel:libasan$secondaryArchSuffix = $libasanLibVersion compat >= $libasanSoVersion
 	devel:libatomic$secondaryArchSuffix = $libatomicLibVersion compat >= $libatomicSoVersion
 	devel:libgcc$secondaryArchSuffix = $libgccLibVersion compat >= $libgccSoVersion
 	devel:libgcc_boot$secondaryArchSuffix = $libgccLibVersion compat >= $libgccSoVersion
@@ -153,6 +162,7 @@ PROVIDES_syslibs_devel="
 	devel:libsupc++$secondaryArchSuffix = $portVersion compat >= 7
 	devel:libsupc++_boot$secondaryArchSuffix = $portVersion compat >= 7
 	devel:libsupc++_kernel$secondaryArchSuffix = $portVersion compat >= 7
+	devel:libubsan$secondaryArchSuffix = $libubsanLibVersion compat >= $libubsanSoVersion
 	"
 REQUIRES_syslibs_devel="
 	gcc${secondaryArchSuffix}_syslibs == $portVersion base
@@ -206,13 +216,15 @@ defineDebugInfoPackage gcc$secondaryArchSuffix \
 	"$(getPackagePrefix fortran)/$relativeInstallDir"/bin/gfortran \
 	"$(getPackagePrefix fortran)/$relativeInstallDir/$gccLibDir"/f951 \
 	"$(getPackagePrefix jit)/$relativeLibDir"/libgccjit.so.$libgccjitLibVersion \
+	"$(getPackagePrefix syslibs)/$relativeLibDir"/libasan.so.$libasanLibVersion \
 	"$(getPackagePrefix syslibs)/$relativeLibDir"/libatomic.so.$libatomicLibVersion \
 	"$(getPackagePrefix syslibs)/$relativeLibDir"/libgcc_s.so.$libgccSoVersion \
 	"$(getPackagePrefix syslibs)/$relativeLibDir"/libgfortran.so.$libgfortranLibVersion \
 	"$(getPackagePrefix syslibs)/$relativeLibDir"/libgomp.so.$libgompLibVersion \
 	"$(getPackagePrefix syslibs)/$relativeLibDir"/libquadmath.so.$libquadmathLibVersion \
 	"$(getPackagePrefix syslibs)/$relativeLibDir"/libssp.so.$libsspLibVersion \
-	"$(getPackagePrefix syslibs)/$relativeLibDir"/libstdc++.so.$libstdcxxLibVersion
+	"$(getPackagePrefix syslibs)/$relativeLibDir"/libstdc++.so.$libstdcxxLibVersion \
+	"$(getPackagePrefix syslibs)/$relativeLibDir"/libubsan.so.$libubsanLibVersion
 
 BUILD()
 {
@@ -236,8 +248,8 @@ BUILD()
 		kernelCcFlags="$kernelCcFlags -mno-red-zone"
 	fi
 
-	"$sourceDir/configure" \
-		--build=$effectiveTargetMachineTriple \
+	 "$sourceDir/configure" \
+	--build=$effectiveTargetMachineTriple \
 		--prefix=$installDir --libexecdir=$installDir/lib --mandir=$manDir \
 		--docdir=$docDir --enable-threads=posix \
 		--disable-nls --enable-shared --with-gnu-ld --with-gnu-as \
@@ -248,7 +260,7 @@ BUILD()
 		--enable-__cxa-atexit --with-system-zlib --enable-checking=release \
 		--with-bug-url=http://dev.haiku-os.org/ \
 		--with-default-libstdcxx-abi=gcc4-compatible \
-		--enable-libssp --enable-host-shared \
+		--enable-libssp --enable-libsanitizer --enable-host-shared \
 		$additionalConfigureFlags
 
 	make $jobArgs
@@ -370,6 +382,17 @@ INSTALL()
 	mkdir -p $developLibDir
 	cd $installDir
 
+	# libasan
+	mv $gccLibDir/libasan.so \
+		$gccLibDir/libasan.so.$libasanSoVersion \
+		$gccLibDir/libasan.so.$libasanLibVersion \
+		$libDir/
+	ln -s $libDir/libasan.so \
+		$libDir/libasan.so.$libasanSoVersion \
+		$libDir/libasan.so.$libasanLibVersion \
+		$gccLibDir
+	rm $gccLibDir/libasan.a
+
 	# libatomic
 	mv $gccLibDir/libatomic.so \
 		$gccLibDir/libatomic.so.$libatomicSoVersion \
@@ -453,6 +476,17 @@ INSTALL()
 	ln -s $libDir/libstdc++.so $libDir/libsupc++.so
 	mv $gccLibDir/libsupc++*.a $developLibDir/
 
+	# libubsan
+	mv $gccLibDir/libubsan.so \
+		$gccLibDir/libubsan.so.$libubsanSoVersion \
+		$gccLibDir/libubsan.so.$libubsanLibVersion \
+		$libDir/
+	ln -s $libDir/libubsan.so \
+		$libDir/libubsan.so.$libubsanSoVersion \
+		$libDir/libubsan.so.$libubsanLibVersion \
+		$gccLibDir
+	rm $gccLibDir/libubsan.a
+
 	# libgcc
 	cp $objectsDir/$effectiveTargetMachineTriple/libgcc/libgcc-kernel.a \
 		$objectsDir/$effectiveTargetMachineTriple/libgcc/libgcc_eh-kernel.a \
@@ -529,7 +563,7 @@ INSTALL()
 
 	# symlink all libraries from libDir -> developLibDir
 	mkdir -p $developLibDir
-	for l in libatomic libgccjit libgomp libquadmath libssp libgcc_s libstdc++ \
+	for l in libasan libatomic libgccjit libgcc_s libgomp libquadmath libssp libubsan libstdc++ \
 			libsupc++; do
 		for f in $libDir/$l*; do
 			symlinkRelative -sfn $f $developLibDir/
@@ -570,6 +604,9 @@ INSTALL()
 		$relativeIncludeDir/libgccjit++.h
 
 	packageEntries "syslibs" \
+		$relativeLibDir/libasan.so \
+		$relativeLibDir/libasan.so.$libasanSoVersion \
+		$relativeLibDir/libasan.so.$libasanLibVersion \
 		$relativeLibDir/libatomic.so \
 		$relativeLibDir/libatomic.so.$libatomicSoVersion \
 		$relativeLibDir/libatomic.so.$libatomicLibVersion \
@@ -590,7 +627,10 @@ INSTALL()
 		$relativeLibDir/libstdc++.so \
 		$relativeLibDir/libstdc++.so.$libstdcxxSoVersion \
 		$relativeLibDir/libstdc++.so.$libstdcxxLibVersion \
-		$relativeLibDir/libsupc++.so
+		$relativeLibDir/libsupc++.so \
+		$relativeLibDir/libubsan.so \
+		$relativeLibDir/libubsan.so.$libubsanSoVersion \
+		$relativeLibDir/libubsan.so.$libubsanLibVersion
 
 	packageEntries "syslibs_devel" \
 		$developLibDir/*.so* \