[patch] Fixup has_pic, has_pie, add has_ssp_all

flago-hases.patch (text/plain), 2.27 KB, created by Kevin F. Quinn (RETIRED) on 2005-04-27 11:38:15 UTC

--- flag-o-matic.eclass.orig	2005-04-27 19:46:05.000000000 +0200
+++ flag-o-matic.eclass	2005-04-27 20:15:50.000000000 +0200
@@ -63,6 +63,22 @@
 # notice: modern automatic specs files will also suppress -fstack-protector-all
 # when only -fno-stack-protector is given
 #
+#### has_pic ####
+# Returns true if the compiler by default or with current CFLAGS
+# builds position-independent code.
+#
+#### has_pie ####
+# Returns true if the compiler by default or with current CFLAGS
+# builds position-independent executables
+#
+#### has_ssp_all ####
+# Returns true if the compiler by default or with current CFLAGS
+# generates stack smash protections for all functions
+#
+#### has_ssp ####
+# Returns true if the compiler by default or with current CFLAGS
+# generates stack smash protections for most vulnerable functions
+#
 
 # C[XX]FLAGS that we allow in strip-flags
 setup-allowed-flags() {
@@ -326,7 +342,6 @@
 	[ "${CFLAGS/-fPIC}" != "${CFLAGS}" ] && return 0
 	[ "${CFLAGS/-fpic}" != "${CFLAGS}" ] && return 0
 	[ "$(echo | $(tc-getCC) ${CFLAGS} -E -dM - | grep __PIC__)" ] && return 0
-	test_version_info pie && return 0
 	return 1
 }
 
@@ -334,9 +349,29 @@
 has_pie() {
 	[ "${CFLAGS/-fPIE}" != "${CFLAGS}" ] && return 0
 	[ "${CFLAGS/-fpie}" != "${CFLAGS}" ] && return 0
-	[ "$(echo | $(tc-getCC) ${CFLAGS} -E -dM - | grep __PIE__)" ] && return 0
-	# test PIC while waiting for specs to be updated to generate __PIE__
-	[ "$(echo | $(tc-getCC) ${CFLAGS} -E -dM - | grep __PIC__)" ] && return 0
+	# Detect pie in default SPECS by building an executable and checking for DYN type
+	# There's no tidy pre-processor definition suitable to find PIE.
+	local temp="$(emktemp)"
+	echo "int main() { return(0); }" > "${temp}.c"
+	$(tc-getCC) -o "${temp}" "${temp}.c" > /dev/null 2>&1
+	local ret=$?
+	if [[ ${ret} == 0 ]]; then
+		local exetype=$(readelf -h ${temp} | grep Type: | awk '{print $2}')
+		if [[ ${exetype} = "DYN" ]]; then
+			ret=0
+		else
+			ret=1
+		fi
+	fi
+	rm -f ${temp} ${temp}.c
+	return ${ret}
+}
+
+# indicate whether code for SSP is being generated for all functions
+has_ssp_all() {
+	# note; this matches only -fstack-protector-all
+	[ "${CFLAGS/-fstack-protector-all}" != "${CFLAGS}" ] && return 0
+	[ "$(echo | $(tc-getCC) ${CFLAGS} -E -dM - | grep __SSP_ALL__)" ] && return 0
 	return 1
 }