Importc: fix glibc aarch64 math.h (dlang#21772)

* importc: Support math.h on glibc aarch64

Signed-off-by: Andrei Horodniceanu <[email protected]>

* compiler/test/compilable/stdcheaders: Reenable math.h on linux aarch64

Signed-off-by: Andrei Horodniceanu <[email protected]>

---------

Signed-off-by: Andrei Horodniceanu <[email protected]>

Author: the-horo

compiler/test/compilable/stdcheaders.c

@@ -19,12 +19,10 @@
 #include <limits.h>
 #include <locale.h>
 
-#if !(defined(__linux__) && defined(__aarch64__)) // /usr/include/bits/math-vector.h(162): Error: undefined identifier `__Float32x4_t`
 #include <math.h>
 #ifndef _MSC_VER // C:\Program Files (x86)\Windows Kits\10\include\10.0.26100.0\ucrt\corecrt_math.h(93): Error: reinterpretation through overlapped field `f` is not allowed in CTFE
 float x = NAN;
 #endif
-#endif
 
 #ifndef _MSC_VER // setjmp.h(51): Error: missing tag `identifier` after `struct
 #include <setjmp.h>
@@ -64,11 +62,9 @@ float x = NAN;
 // Apple: /Applications/Xcode-14.2.0.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk/usr/include/tgmath.h(39): Error: named parameter required before `...`
 // OpenBSD: /usr/lib/clang/13.0.0/include/tgmath.h(34): Error: named parameter required before `...`
 // Linux: /tmp/clang/lib/clang/15.0.3/include/tgmath.h(34): Error: named parameter required before `...`
-#if !(defined(__linux__) && defined(__aarch64__)) // /usr/include/bits/math-vector.h(162): Error: undefined identifier `__Float32x4_t`
 #include <tgmath.h>
 #endif
 #endif
-#endif
 
 #ifndef __linux__
 #ifndef __APPLE__

druntime/src/__importc_builtins.di

@@ -111,3 +111,10 @@ version (DigitalMars)
         ulong a, b;
     }
 }
+
+version (CRuntime_Glibc) version (AArch64)
+{
+    // math.h needs these
+    alias __Float32x4_t = __vector(float[4]);
+    alias __Float64x2_t = __vector(double[2]);
+}

druntime/src/importc.h

@@ -186,8 +186,16 @@ typedef unsigned long long __uint64_t;
 #define _Float128 long double
 #define __float128 long double
 #endif
+
+#ifdef __aarch64__
+// glibc's math.h needs these types to be defined
+typedef struct {} __SVBool_t;
+typedef struct {} __SVFloat32_t;
+typedef struct {} __SVFloat64_t;
 #endif
 
+#endif // __linux__
+
 #if __APPLE__
 #undef __SIZEOF_INT128__
 #endif