Test that g++ and Clang++ can compile assembly

When there's no C compiler available

test cases/common/127 cpp and asm/meson.build

@@ -0,0 +1,16 @@
+project('c++ and assembly test', 'cpp')
+
+sources = ['trivial.cc']
+# If the compiler cannot compile assembly, don't use it
+if meson.get_compiler('cpp').get_id() != 'msvc'
+  cpu = host_machine.cpu_family()
+  sources += ['retval-' + cpu + '.S']
+  cpp_args = ['-DUSE_ASM']
+  message('Using ASM')
+else
+  cpp_args = ['-DNO_USE_ASM']
+endif
+
+exe = executable('trivialprog', sources,
+  cpp_args : cpp_args)
+test('runtest', exe)

test cases/common/127 cpp and asm/retval-arm.S

@@ -0,0 +1,8 @@
+#include "symbol-underscore.h"
+
+.text
+.globl SYMBOL_NAME(get_retval)
+
+SYMBOL_NAME(get_retval):
+	mov	r0, #0
+	mov	pc, lr

test cases/common/127 cpp and asm/retval-x86.S

@@ -0,0 +1,8 @@
+#include "symbol-underscore.h"
+
+.text
+.globl SYMBOL_NAME(get_retval)
+
+SYMBOL_NAME(get_retval):
+	xorl	%eax, %eax
+	retl

test cases/common/127 cpp and asm/retval-x86_64.S

@@ -0,0 +1,8 @@
+#include "symbol-underscore.h"
+
+.text
+.globl SYMBOL_NAME(get_retval)
+
+SYMBOL_NAME(get_retval):
+	xorl	%eax, %eax
+	retq

test cases/common/127 cpp and asm/symbol-underscore.h

@@ -0,0 +1,5 @@
+#if defined(__WIN32__) || defined(__APPLE__)
+# define SYMBOL_NAME(name) _##name
+#else
+# define SYMBOL_NAME(name) name
+#endif

test cases/common/127 cpp and asm/trivial.cc

@@ -0,0 +1,16 @@
+#include<iostream>
+
+extern "C" {
+  int get_retval(void);
+}
+
+int main(int argc, char **argv) {
+  std::cout << "C++ seems to be working." << std::endl;
+#if defined(USE_ASM)
+  return get_retval();
+#elif defined(NO_USE_ASM)
+  return 0;
+#else
+  #error "Forgot to pass asm define"
+#endif
+}