Improved comments on the work-around to the GCC x86 floating point wonkiness.

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manifest

@@ -1,5 +1,5 @@
-C Work\saround\sfor\san\sapparent\sGCC\sbug.\s\sSee\n[forum:/info/ee7278611394034c|forum\spost\see7278611394034c]\sfor\sdetails.
-D 2023-07-05T18:59:52.671
+C Improved\scomments\son\sthe\swork-around\sto\sthe\sGCC\sx86\sfloating\spoint\swonkiness.
+D 2023-07-05T19:56:14.847
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@@ -705,7 +705,7 @@ F src/trigger.c ad6ab9452715fa9a8075442e15196022275b414b9141b566af8cdb7a1605f2b0
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manifest.uuid

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src/util.c

@@ -387,9 +387,20 @@ u8 sqlite3StrIHash(const char *z){
 }
 
 /*
-** Work around an apparent bug in GCC.
+** Work around an issue in GCC where it generates code that stores
+** intermediate results to a higher precision than binary64.  This
+** messes up the Dekker algorithm.  See the discussion at
 ** https://sqlite.org/forum/info/ee7278611394034c
+**
+** By adding the -ffloat-store option, it forces GCC to truncate
+** intermediate results to the correct precision.  The GCC devs
+** recommended -fexcess-precision=standard or -std=c99.  Those options
+** work too, from the command-line, but I could not get them to work
+** as a #pragma.  We want the "sqlite3.c" to "just work" without
+** requiring any special compiler-options, so we continue to use
+** the -ffloat-store method of working around the issue.
 */
+
 #ifdef i386
 #pragma GCC push_options
 #pragma GCC optimize("float-store")
@@ -423,7 +434,7 @@ static void dekkerMul2(double *x, double y, double yy){
   x[1] += cc;
 }
 
-/* End of the GCC bug work-around */
+/* End of the GCC x86 floating-point work-around */
 #ifdef i386
 #pragma GCC pop_options
 #endif