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-rw-r--r--gnulib-m4/asm-underscore.m471
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+# asm-underscore.m4 serial 3
+dnl Copyright (C) 2010-2017 Free Software Foundation, Inc.
+dnl This file is free software; the Free Software Foundation
+dnl gives unlimited permission to copy and/or distribute it,
+dnl with or without modifications, as long as this notice is preserved.
+
+dnl From Bruno Haible. Based on as-underscore.m4 in GNU clisp.
+
+# gl_ASM_SYMBOL_PREFIX
+# Tests for the prefix of C symbols at the assembly language level and the
+# linker level. This prefix is either an underscore or empty. Defines the
+# C macro USER_LABEL_PREFIX to this prefix, and sets ASM_SYMBOL_PREFIX to
+# a stringified variant of this prefix.
+
+AC_DEFUN([gl_ASM_SYMBOL_PREFIX],
+[
+ dnl We don't use GCC's __USER_LABEL_PREFIX__ here, because
+ dnl 1. It works only for GCC.
+ dnl 2. It is incorrectly defined on some platforms, in some GCC versions.
+ AC_REQUIRE([gl_C_ASM])
+ AC_CACHE_CHECK(
+ [whether C symbols are prefixed with underscore at the linker level],
+ [gl_cv_prog_as_underscore],
+ [cat > conftest.c <<EOF
+#ifdef __cplusplus
+extern "C" int foo (void);
+#endif
+int foo(void) { return 0; }
+EOF
+ # Look for the assembly language name in the .s file.
+ AC_TRY_COMMAND(${CC-cc} $CFLAGS $CPPFLAGS $gl_c_asm_opt conftest.c) >/dev/null 2>&1
+ if LC_ALL=C grep -E '(^|[[^a-zA-Z0-9_]])_foo([[^a-zA-Z0-9_]]|$)' conftest.$gl_asmext >/dev/null; then
+ gl_cv_prog_as_underscore=yes
+ else
+ gl_cv_prog_as_underscore=no
+ fi
+ rm -f conftest*
+ ])
+ if test $gl_cv_prog_as_underscore = yes; then
+ USER_LABEL_PREFIX=_
+ else
+ USER_LABEL_PREFIX=
+ fi
+ AC_DEFINE_UNQUOTED([USER_LABEL_PREFIX], [$USER_LABEL_PREFIX],
+ [Define to the prefix of C symbols at the assembler and linker level,
+ either an underscore or empty.])
+ ASM_SYMBOL_PREFIX='"'${USER_LABEL_PREFIX}'"'
+ AC_SUBST([ASM_SYMBOL_PREFIX])
+])
+
+# gl_C_ASM
+# Determines how to produce an assembly language file from C source code.
+# Sets the variables:
+# gl_asmext - the extension of assembly language output,
+# gl_c_asm_opt - the C compiler option that produces assembly language output.
+
+AC_DEFUN([gl_C_ASM],
+[
+ AC_EGREP_CPP([MicrosoftCompiler],
+ [
+#ifdef _MSC_VER
+MicrosoftCompiler
+#endif
+ ],
+ [gl_asmext='asm'
+ gl_c_asm_opt='-c -Fa'
+ ],
+ [gl_asmext='s'
+ gl_c_asm_opt='-S'
+ ])
+])