[libc] Fix memory leak in MPFRWrapper cospif with MPFR pre 4.2.

[lntue]

No description provided.

[llvmbot]

@llvm/pr-subscribers-libc

Author: None (lntue)

Changes

---

Full diff: https://github.com/llvm/llvm-project/pull/114415.diff

1 Files Affected:

• (modified) libc/utils/MPFRWrapper/MPFRUtils.cpp (+2-1)

diff --git a/libc/utils/MPFRWrapper/MPFRUtils.cpp b/libc/utils/MPFRWrapper/MPFRUtils.cpp
index 60e4abadb5e3c8..4fa6d2f9291993 100644
--- a/libc/utils/MPFRWrapper/MPFRUtils.cpp
+++ b/libc/utils/MPFRWrapper/MPFRUtils.cpp
@@ -262,6 +262,7 @@ class MPFRNumber {
 
       int d = mpz_tstbit(integer, 0);
       mpfr_set_si(result.value, d ? -1 : 1, mpfr_rounding);
+      mpz_clear(integer);
       return result;
     }
 
@@ -271,7 +272,7 @@ class MPFRNumber {
     mpfr_cos(result.value, value_pi.value, mpfr_rounding);
 
     return result;
-#endif
+// #endif
   }
 
   MPFRNumber erf() const {

[nickdesaulniers]

If this was fixed in a newer version of MPFR, consider adding a link to the commit in the PR description, and a comment to the sources if this statement should be removed at some point.

[lntue]

If this was fixed in a newer version of MPFR, consider adding a link to the commit in the PR description, and a comment to the sources if this statement should be removed at some point.

Unfortunately, this is a bug in our wrapper, not on MPFR side. With newer MPFR, we just call the cospi function directly and there is no bug there.