[libc] Capture 'POLY_COEFFS' by reference in asinpi_polyeval lambda.

[renhiyama]

Closes #164403

GCC fails to compile libc currently. This PR fixes this by capturing 'POLY_COEFFS' by reference

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[llvmbot]

@llvm/pr-subscribers-libc

Author: Ren Hiyama (renhiyama)

Changes

Closes #164403

---

Full diff: https://github.com/llvm/llvm-project/pull/164404.diff

1 Files Affected:

• (modified) libc/src/math/generic/asinpif16.cpp (+1-1)

diff --git a/libc/src/math/generic/asinpif16.cpp b/libc/src/math/generic/asinpif16.cpp
index aabc0863ba527..395f4c4ebc070 100644
--- a/libc/src/math/generic/asinpif16.cpp
+++ b/libc/src/math/generic/asinpif16.cpp
@@ -77,7 +77,7 @@ LLVM_LIBC_FUNCTION(float16, asinpif16, (float16 x)) {
   };
   // polynomial evaluation using horner's method
   // work only for |x| in [0, 0.5]
-  auto asinpi_polyeval = [](double x) -> double {
+  auto asinpi_polyeval = [&](double x) -> double {
     return x * fputil::polyeval(x * x, POLY_COEFFS[0], POLY_COEFFS[1],
                                 POLY_COEFFS[2], POLY_COEFFS[3], POLY_COEFFS[4],
                                 POLY_COEFFS[5], POLY_COEFFS[6], POLY_COEFFS[7]);

[DavidSpickett]

I know you said this in the issue, but the PR description should also say why this is being done. Some people will only see this via the git logs later.

Compiler Explorer link for reference: https://godbolt.org/z/bo44Kz6da

(and otherwise I leave it to the libc team to review)

[renhiyama]

I know you said this in the issue, but the PR description should also say why this is being done. Some people will only see this via the git logs later.

Compiler Explorer link for reference: https://godbolt.org/z/bo44Kz6da

(and otherwise I leave it to the libc team to review)

I see, I didn't knew about that - sorry. I have updated the PR description stating that currently GCC cannot build libc, and this PR fixes this by by capturing 'x' by reference. Hopefully this clears the problem!

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