[flang-commits] [flang] [flang] Warn when F128 is unsupported (PR #102147)

[Slava Zakharin via flang-commits]

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@@ -462,8 +509,10 @@ end function ieee_real_a##AKIND##_i##KKIND;
   interface ieee_real
     SPECIFICS_I(IEEE_REAL_I)
     SPECIFICS_R(IEEE_REAL_R)
+#if FLANG_SUPPORT_R16
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vzakhari wrote:

I believe these intrinsics may work for targets where `LDBL_MANT_DIG != 113` (e.g. x86).  They can be folded by Flang given that `libquadmath` is linked to the compiler itself. They can also execute in runtime, because they will be lowered to "basic" float128 operations that LLVM backend may support for the target (e.g. x86).

Maybe we can just issue a warning about incomplete real*16 support and do not change the module file?

https://github.com/llvm/llvm-project/pull/102147