fix bug when error is infinite (#46436)

(cherry picked from commit c491e79)
JuliaLang · Aug 26, 2022 · 0b840c7 · 0b840c7
1 parent 649f568
commit 0b840c7
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Showing 2 changed files with 3 additions and 2 deletions.
diff --git a/base/math.jl b/base/math.jl
@@ -1068,8 +1068,8 @@ end
         xnlo += err
         n >>>= 1
     end
-    !isfinite(x) && return x*y
-    return muladd(x, y, muladd(y, xnlo, x*ynlo))
+    err = muladd(y, xnlo, x*ynlo)
+    return ifelse(isfinite(x) & isfinite(err), muladd(x, y, err), x*y)
 end
 
 function ^(x::Float32, n::Integer)

diff --git a/test/math.jl b/test/math.jl
@@ -1362,6 +1362,7 @@ end
     end
     # test for large negative exponent where error compensation matters
     @test 0.9999999955206014^-1.0e8 == 1.565084574870928
+    @test 3e18^20 == Inf
 end
 
 # Test that sqrt behaves correctly and doesn't exhibit fp80 double rounding.