project: custom config: test for x87, x64, and IEEE properties at config time.

1 files changed, 44 insertions, 0 deletions

diff --git a/project/config/cfgdefs.sh b/project/config/cfgdefs.sh
index 560afa6..adbfc33 100644
--- a/project/config/cfgdefs.sh
+++ b/project/config/cfgdefs.sh
@@ -141,6 +141,50 @@ cfgdefs_perform_common_tests()
 	mb_cfgtest_headers='pthread.h'
 	cfgtest_type_size 'pthread_t'
 
+	# toolchain
+	cfgtest_newline
+	cfgtest_comment 'toolchain'
+
+	# x87
+	mb_code_snippet=''
+	mb_code_snippet="$mb_code_snippet "'void fn(void)'
+	mb_code_snippet="$mb_code_snippet "'{__asm__ __volatile__ ("fnstcw pcw");'
+	mb_code_snippet="$mb_code_snippet "' __asm__ __volatile__ ("fldcw  pcw");}'
+
+	if cfgtest_code_snippet "$mb_code_snippet"; then
+		cfgtest_cflags_append '-DHAVE_GCC_ASM_FOR_X87'
+	fi
+
+	# x64
+	mb_code_snippet=''
+	mb_code_snippet="$mb_code_snippet "'void fn(void)'
+	mb_code_snippet="$mb_code_snippet "'{__asm__ __volatile__ ("callq *%rax");}'
+
+	if cfgtest_code_snippet "$mb_code_snippet"; then
+		cfgtest_cflags_append '-DHAVE_GCC_ASM_FOR_X64'
+	fi
+
+	# IEEE 754: little endian / big endian
+	if $mb_cfgtest_cc -E -dM - < /dev/null \
+			| grep '__BYTE_ORDER__ __ORDER_LITTLE_ENDIAN__' \
+			> /dev/null; then
+		cfgtest_cflags_append '-DDOUBLE_IS_LITTLE_ENDIAN_IEEE754'
+
+	elif $mb_cfgtest_cc -E -dM - < /dev/null \
+			| grep '__BYTE_ORDER__ __ORDER_BIG_ENDIAN__' \
+			> /dev/null; then
+		cfgtest_cflags_append '-DDOUBLE_IS_BIG_ENDIAN_IEEE754'
+
+	else
+		cfgtest_newline
+		cfgtest_comment 'cfgdefs.sh: cannot detect little/big endian,'
+		cfgtest_comment 'cfgtest.sh: so defined both macros below.'
+		cfgtest_newline
+
+		cfgtest_cflags_append '-DDOUBLE_IS_LITTLE_ENDIAN_IEEE754'
+		cfgtest_cflags_append '-DDOUBLE_IS_BIG_ENDIAN_IEEE754'
+	fi
+
 	# getrandom: easier to simply test,
 	# than to test whether we need to test
 	# (and then test).